N/L A

National Aeronautics and

Space Administration

Lyndon B. Johnson

Space Center

Houston, Texas

Research

and

Technology

Annual Report

FY- 1980

F

N2

C.
Itr
National Aeronautics and

Space Administration

Lyndon B. Johnson Space Center

Houston, Texas

77058

The charge.out number_A,_:://essi_ NO.) fo,t.i, book "/

ii .a UL

N/ A

Rep_toA"_ol AT2

Dr. A. M. Lovelace

Deputy Administrator

National Aeronautics

and Space Administration

Washington, DC 20546

Dear Al:

Enclosed are two copies of the annual Johnson Space Center R&T Report

prepared in accordance with your request. For additional information

or copies, contact M. E. Goodhart, Code AT2.

Sincerely, /_

K

Director

Encl osures

cc:

NASA Hqs., Mr. T. W. Chappelle, LB4 - lO cys

Mr. W. E. Lilly, B

Mr. W. C. Williams, D

Dr. A. J. Calio, E- lO cys

Mr. J. F. Yardley, M - IO cys

Dr. S. I. Weiss, 0

Dr. W. B. Olstad, R - lO cys

Mr. A. J. Stofan, S - lO cys

Mr. R. E. Smylie, T - 2 cys

Ms. S. Wilson, LG-2 - lO cys

Mr. S. J. Evans, H

ARC, Mr. C. A. Syvertson, DD 2 cys

DEFC, Mr. I. T. Gillam, OD - 2 cys

GSFC, Mr. A. T. Young, lO0 - 2 cys

JPL, Dr. B. C. Murray, 180-905 - 2 cys

KSC, Mr. R. G. Smith, CS - 2 cys

LaRC, Mr. D. P. Hearth, 106 - 2 cys

LeRC, Dr. John McCarthy, OlO0 - 2 cys

MSFC, Dr. W. R. Lucas, DAOI - 2 cys

NSTL, Mr. J. Hlass 2 cys

WFC, Mr. R. L. Krieger, OD - 2 cys

Research

and

Technology

Annual Report

FY-1980

JSC-16993

Space Transportation Systems

Aeronautics and Space Technology

Space and Terrestrial Applications

Space Sciences

Prepared by

Program Planning Office

Technical P_anning Office

Code: AT

November 1980

Preface

cSarr,_'-out number [Accession

,

!o, this book is ,/_. _'-f _/

The charge.out number IAccesslon No.)

ior this boqll_isJSreDort is prepared on an annual

basis for the purposes ot mgnllgt,[i,_u

the fiscal year research and technology

(R&T) activities. Its intent is to better

NO.'J inform the R&T Program Managers of

significant accomplishments that

promise practical and beneficial program application. The report is not inclusive of all R&T activities.

The document is organized into two

distinct sections: (1) a general summary of the major R&T activities in each

program area, and (2) a description of

significant individual completed activities and their results.

This document will be updated

November 1 of each year.

The JSC Annual R&T Report is compiled by the Technical Planning Office,

Office of the Center Director. The personnel listed below have coordinated

the technical inputs for their respective

sections of the report. Detailed questions may be directed to them or to the

technical monitors listed in the Significant Task indices.

M. E. Goodhart/Code AT2

713-483-2703

L. C. Krchnak/Code AT2

713-483-2703

G A. Nixon/Code SA

713-483-2539

Dr. J. L. Warner/Code SA

713-483-2781

iuP, t11_,/

L

.... L.7,?&'. ...

# I

Space Transportation Systems

Aeronautics and Space Technology

Space and Terrestrial Applications

Space Sciences

OHNSON SPACE CENT_

HouSTON, TEXAS

iii

Index

Summaries 1

3

7

11

15

Office of Space Transportation Systems

Office of Aeronautics and Space Technology

Office of Space and Terrestrial Applications

Office of Space Sciences

Significant

Tasks

19

21

37

59

75

Office of Space Transportation Systems

Office of Aeronautics and Space Technology

Office of Space and Terrestrial Applications

Office of Space Sciences

v

Summaries

Office of

Space

Transportation

Systems

Summary

The Space Transportation System

(STS) fiscal year 1981 activities plan

highlights the establishment of permanent manned occupancy in low

Earth orbit as the overriding goal for

the 1980's with this capability to be

expanded by a manned geosynchronous-Earth-orbit facility in the

1990's. Inherent in these goals are

several time-phased STS augmentations as shown in the evolution table

(table I). The Johnson Space Center

(JSC) plays a major role in the definition and development of these

capabilities. The research and technology activities sponsored by the Advanced Programs Office are divided

into two major categories. The first

category is that of major systems

studies, which pursues the definition

of augmentations to the Space

Transportation Systems that are required to support new initiatives identified in the activity plan. These

studies are carried from preliminary

phase A analyses through phase B

project definition. The second major

Transportation

Services

Platforms

Facilities

TABLE I._EVOLUTION OF SPACE TRANSPORTATION SYSTEMS NEEDS

Goal: Permanent/manned occupancy of low Earth orbit Goal: Operation of manned

geosynchronous facility

1980 to 1985

Objective: routine operation of Shuttle/

Spacelab Inertial Upper Stage, Spinning

Solid Upper Stage, and Manned

Maneuvering Unit

• Augment STS operational capability

Power Extension Package (PEP)

Shuttle thrust augmentation

• High-energy Solar Electric

Propulsion System (SEPS)

• Orbiter health determination

• Satellite services near Orbiter

(placement, retrieval, module

replacement)

• Large structures experiments definition

• Free-flying power modules,

experiment platforms, and

materials processing modules

(unmanned/STS-tended)

1985 to 1990

Objective: permanent facility in low

Earth orbit

• High-performance upper stage

such as advanced Centaur

Adapters, tools, and devices for

operations using Orbiter Remote

Manipulator System

Maintenance and repair of satellites

in sight of Orbiter

Satellite services remote from Orbiter

(placement, retrieval, module replacement)

• Large structures experiments and

demonstrations

• Low-Earth-orbit facility with service,

habitation, flight support, and

construct,on capability

1990 to 2000

Objective: geosynchronous facility

• Orbital transfer vehicle (OIV)

• Crew capsule (MOTV)

• Shuttle-derived heavy-lift

launch vehicle (HLLV)

• Service systems for routine

operations remote from Orbiter

Ln geosynchronous orbit

• Large power module

• Permanent mannable facility qn

geosynchronous orbit
category of activity encompasses supporting studies to identify subsystem

hardware and software requirements

and to carry those subsystem developments through breadboard and prototype demonstrations.

The bulk of the current JSC

research and technology activity is

centered on those objectives for the

1980 to 1985 time frame. Specific

areas of near-term high priority include

those of satellite services near the Orbiter and Shuttle augmentation. For

the 1985 to 1990 time frame, the

Space Operations Center (SOC) lowEarth-orbit manned facility is the highest priority new initiative. The following paragraphs highlight the current

in-house and funded activities in support of these goals.

Satellite Services Near Orbiter

Satellite services is a high-priority

evolutionary program at JSC. The

baseline STS, through the use of the

Remote Manipulator System (RMS),

the Extravehicular Mobility Unit (EMU),

and the Manned Maneuvering Unit

(MMU), will offer users the capability

to deploy and retrieve satellites and to

provide limited payload services.

Future near-term payloads are expected to require much more extensive supporting services that will

necessitate longer extravehicular activity (EVA) periods and more extensive astronaut support equipment and

service tools. The spectrum of activities that is expected to be required

in the mid- to late-1980's is shown in

figure 1.

The specific activities underway at

JSC fall into both the major system

studies and the supporting studies and

advanced development categories.

Two parallel studies are the augmenting of in-house activities aimed at

identifying satellite services requirements and the specific hardware

necessary to satisfy these requirements. Additional activities are underway to design, develop, and test prototype hardware that has already been

determined to be a vital part of the

satellite services program.

Two key hardware elements, reported in more detail in the text of this

report, are the open cherrypicker

(OCP) (fig. 2) and the Maneuverable

Television (MTV) (fig. 3). The OCP will

Figure 1.--Near Orbiter satellite serviceselements.

Figure 2.--The opencherrypicker,

Figure3.--The ManeuverableTelevision.

oeO eee°

_ • • • • 2 TV CAMERAS WITH DUAL-CHANNEL CAPABILITY

"_""_'_'_,_lr"'x, • • • COMMUNICAT IONS THROUGH ORBITER

_;_n_a_ • • OPERATING RANGE - 3219 METERS (2 MILES)

_e • MINIMUM&v- DIFFERENTIAL VELOCITY :

ee• 0.003 M/S CO.OlFT S_

• • •. • SIZE - 84 BY 84 BY 109 CENTIMETERS

" • • (33 BY 33 BY 43 INCHES_

_ ego • WEIGHT - 272 KILOGRAMS (600 POUNDS)

441t'° • • " &'_

OBSERVATION ON-THE-GROUND

FROM ORBITER REMOTE DIAGNOSTICS
provide the astronaut with a stable

work station from which to access and

service payloads that are attached in

or near the payload bay. The OCP is

attached to the end of the Remote

Manipulator System and thus augments both the utility of the RMS and

the capability of the astronaut to perform useful work. The MTV is a small

free-flying television that will provide

a vital inspection function in the nearOrbiter vicinity to determine the status

of payloads before berthing with the

Orbiter and to provide monitoring

capability during satellite servicing.

Additional capabilities and equipment

that are being considered include zero

prebreath suits to reduce EVA overhead, handling and positioning aids to

provide access to payloads, and

special tools to accomplish detailed

service tasks.

Shuttle Augmentation

Shuttle augmentation activities for the

next several years wilt concentrate on

increasing the Space Shuttle

capabilities, decreasing the weight

and cost, enhancing reliability and

safety, and reducing ground turnaround time. JSC continues an active

research and technology program

aimed at these areas to bring the STS

to a routine operational status.

One major concern of the Space

Shuttle payload community is the

limited capability of the Orbiter for

user onorbit energy requirements. For

the last several years, a major portion

of the JSC advanced programs activities has been the pursuit of augmenting this power capability. The

Power Extension Package (PEP) (fig.

4) is a fiscal year 1982 new initiative

that promises both increased user

power and extended mission duration.

It is an easily installed lightweight

mission kit consisting of two deployaprogress was achieved in expanding

the PEP performance data base addressing these variables. Results have

been published with a complete

description of the PEP design and

operational characteristics in a convenient "PEP User's Handbook." This

handbook highlights the major

benefits of PEP starting with the increased power it offers payloads, the

associated increase in electrical

energy that allows mission extensions

of two to three times the Orbiter

baseline of 7 days, and its enhancement of Orbiter heat-rejection capacity resulting from reduction in fuel cell

waste heat generation. Other major

benefits are described including comanifesting opportunities, all-altitude

and all-inclination flight regimes,

quick installation and removal of

payloads for fast mission turnaround,

light weight, and compact packaging.

Through an intercenter agreement,

JSC and Lewis Research Center have

initiated the development of largearea low-cost solar cells for application in the PEP program. The goal of

this development is to achieve a

reduction in solar cell procurement

costs from current levels of approximately Sl00/watt to S30/watt. In this

development, two solar cell vendors

Figure 4.--The Power Extension Package.

bte solar arrays that augment the :_. _I

cryogenic fuel cell power system. A ;

typical PEP mission at 55 ° orbital in- _ .

clination would provide an increase in

user power to 15 kilowatts from the

nominal 7 kilowatts while increasing

potential mission duration to 20 days.

PEP performance is influenced by

several mission-planning variables including altitude, inclination, launch

date, launch time, orientation, and required power level. Significant

will develop wraparound contact cells

as well as conventional top/bottom

contact cells. Phase 1 of this activity

(cell development and production

readiness) will be completed by June

1981, at which time phase 2 (production verification) will begin. Both

phases of the activity are scheduled to

be completed before the initiation of

PEP hardware development.

Another area of operational concern

as mission durations increase is that of

atmospheric revitalization. The Space

Shuttle uses expendable lithiumhydroxide canisters for carbon dioxide

removal. Mission durations in excess

of 7 days with this system would impose severe stowage problems as well

as increase weight penalties. A prime

candidate for early incorporation is the

regenerable solid amine carbon dioxide removal system that has been

developed under the advanced

development funding. Also high on the

priority list for Shuttle enhancement is

'the Solid Polymer Electrolyte (SPE)

fuel cell. The solid polymer fuel cell

will provide an order of magnitude increase over the current fuel cell

system. This system augmentation

promises both cost and weight savings

and considerably reduces ground turnaround requirements.
Space Operations Center

The Johnson Space Center continues

in its role of principal proponent of a

permanently manned low-Earth-orbit

facility. A prime candidate for such a

facility is the Space Operations Center

(fig. 5). The SOC is intended to provide a permanent base for the construction of large structures, the servicing of orbital transfer vehicles and

satellites, and the provisioning of

scientific and medical endeavors. The

concept was developed and analyzed

by a JSC in-house study team in fiscal

year t979. In fiscal year 1980, studies

were awarded to industry to provide

further configuration definition and

systems analysis and to define and

analyze the interaction of the SOC

with the Space Transportation System.

The JSC team that participated _n

the concept definition has been expanded and is now comprised of some

20 specialists covering all areas of

system and subsystem design and

analysis, operations, and programmatics and costs. In addition to supporting the technical management of

the contracted studies, this group is

continuing in-house tasks that reinforce the industry study efforts. It is

also a key participant in the program

planning activities that are developing

the various options available to establish a manned operational facility by

the end of the decade. The SOC is

currently proposed as a new initiative

for fiscal year 1985 with initial operational capability in 1988.

Figure 5.--Space Operations Center.

6
Office of

Aeronautics and

Space

Technology

Summary

The activities at Johnson Space

Center (JSC) funded by the Office of

Aeronautics and Space Technology

(OAST) involve aeronautical, space,

and energy research and technology

(R&T) development. These research

and technology areas encompass

future developments of all NASA program offices as well as other Government agencies. The use of the Space

Shuttle Orbiter as an experimental

vehicle, the development of spacebased power satellites to beam energy

to Earth, the electrolysis cell/fuel cell

orbital energy storage systems, the

advanced onboard propulsion technology and the large space systems

technology are areas of continuing

JSC interest and activity.

The major activities in space

research and technology at JSC during

fiscal year 1980 were (1) support to

the Orbiter Experiments Program for

which JSC continues to provide overall

integration management and program

planning, technical development for

specific experiments (including

development of supporting equipment), and integration of experiments

into the Orbiter; (2) in-house and

funded system definition studies of

the solar power satellite (SPS) system

that would generate terrestrial electric

power from orbiting SPS systems; (3)

large-capacity orbital energy storage

systems research and technology,

which include electrolysis cell/fuel

cell development, laboratory modeling

of space plasma environmental interactions of large high-voltage solar

arrays in the large vacuum chamber,

and development of advanced thermal

management systems for space use;

(4) advanced onboard propulsion

technology; (5) advanced synthetic

aperture radar; and (6) large space

systems technology to lower cost of

space assembly, fabrication, or

deployment of large space systems.

Another major area of continuing JSC

activity is the transfer of Shuttlerelated technology developments to

an all new technology airplane with

lower weight and reduced operational

cost.

Experimental Programs

The Orbiter Experiments Program will

use the Space Shuttle Orbiter as a

flight research vehicle to obtain inflight data over a broad flight spectrum

for a variety of technology disciplines

(fig. 1). As the lead center for the overall project, JSC is responsible for project management and integration of

various Orbiter experiments. These experiments are designed to augment

the research and technology data

base for design verification of current

and future vehicles by collecting Shuttie flight data in related technology

disciplines and to verify, correlate, and

extrapolate data derived from groundbased facilities with the flight data.

Solar Power Satellite

JSC in-house and contractor studies

have shown that space generation and

transmission of solar power is an attractive candidate for augmenting terrestrial fossil-fueled electric power

generation plants in the future. As a

result of these studies, NASA and the

Department of Energy (DOE) initiated

the Solar Power Satellite Concept

Development and Evaluation Program.

This evaluation program is guided by a

joint DOE-NASA plan that covers the

period from mid-1977 to mid-1980.

Figure 1 .--Shuttle mission experiment opportunities.

AEROTHERMOOYNAMICS

STRUCTURES & MATERIALS

FUGHT CONTROLS

PROPU_ON

STRUCTURES & M z'Tt-R A S

_: RO THERMODYNAMICS

FUGHT CONTROLS

STRUCTURES ,_ MATERIALS

_,,= ,,r

• "rE

_,T_*_C_JI_E > • MATLRb_LS
The overall objective of this program is to conceptually define a

reference system (fig. 2) and to understand the economic practicality and

the social and environmental acceptability of the SPS system. The program

is divided into four major components:

system definition: environment,

health, and safety; socioeconomic

issues; and comparative assessment.

NASA is responsible for conducting

the system definition activity and the

DOE is responsible for the other three.

The objective of the activity at JSC is

to conceptually define a reference

SPS system and to identify alternative

technologies within the reference concept. The four major elements of the

JSC activity are as follows:

1. Energy conversion in space

2. Power transmission to Earth

3. Space transportation

4. Space construction

The first milestone of the joint DOENASA plan was completed with the

delivery of the Reference System

Document in October 1978. The DOE

has made extensive use of these data

to perform environmental, comparative, and socioeconomic assessments.

In 1979, JSC continued system definition studies to iterate design of the

reference concept with major

emphasis on updating the system

concept, optimizing the construction

and maintenance approach, defining

the industrial and Earth transportation

complex, defining the total SPS operations, defining the SPS integration

with the grid network, preparing technology advancement plans, and performing cost and schedule analyses.

The major study areas for fiscal year

1980 include the following.

1. Summary reports were submitted to DOE in support of the SPS Program Assessment Report that is being

prepared by DOE.

2. Workshops were conducted in

the technical areas of microwave

power transmission, space structures

and construction, energy conversion

and power management, and space

transportation.

3. System definition studies were

conducted with emphasis on costing

the reference system and on defining

alternative concepts that included

laser-power transmission, reducedsize cargo launch vehicles, and solidstate microwave systems.

4. Critical supporting investigations were completed in the areas of

(a) solid-state combining device

assessment (which allows the combination of several low-power solidstate devices into an efficient highdensity microwave generator), (b)

fiber optics investigations (for phasecontrol system circuits), (c) evaluation

of a retrodirective phase-control

breadboard system, and (d) the SPS

microwave/ionosphere interaction experiment.

The results of the ionosphere heating experiment indicate that the 23-

mW/cm 2 power density limit for the

microwave beam is too conservative

and could be raised. Effects produced

by simulated SPS ionosphere heating

are many times less than natural

ionospheric disturbances as introduced by solar flares. The ionospheric

power density limit is a critical SPS

system sizing parameter and has a

significant impact on the cost. A higher limit allows more power to be

delivered to a smaller rectenna.

Three additional efforts that also

support the SPS study are (1) large

space systems technology, (2) space

plasma interaction experiments for

large power systems, and (3) a continuing study of techniques to use

lunar materials for space construction.

Integrated Orbital Energy

System

Advances in critical space power

research and technology at JSC in fiscal year 1980 include (t) low-cost

solar arrays in support of the Orbiter

Power Extension Package, (2) highcapacity energy storage based on the

Solid Polymer Electrolyte membrane

fuel cell, (3) thermal management of

onorbit energy systems, and (4)

modeling of space plasma environmental interaction of large highvoltage solar arrays.

A subauthorization from Lewis

Research Center aided in developing

low-cost solar cells for the Power Extension Package Solar Array being

developed by JSC with sponsorship by

the Office of Space Transportation

Systems.

The regenerative fuel ce I/

electrolysis celt integrated energy

system involves development of technology with many applications. With

readily available water as the resupply

commodity, it is a prime candidate as

the preferred energy system for any

extended duration manned or unmanned orbiting spacecraft. From

Shuttle-supplied water, this system

Figure 2.--Artist's concept of thereference solarpower satellite system.
can also be used for orbital manufacture of propellants for orbital transfer

vehicles. It is ideally suited for space

platforms in which experiments could

draw power and/or hydrogen or oxygen

for propellants, for feedstock for space

manufacturing processes, or for life

support use as required. Thus, the

system serves as an orbiting utility

substation.

Research and technology in integrating thermal management concepts for onorbit power systems was

originally initiated by the Office of

Space Transportation Systems. Joint

funding was provided by the Office of

Space Transportation Systems and the

Office of Aeronautics and Space Technology in fiscal year 1980. The Office

of Aeronautics and Space Technology

wilt continue to sponsor the effort in

fiscal year 1981 and beyond. The work

in fiscal year 1980 provided a

feasibility demonstration of the dualpassage high-performance heat pipe

design that forms the basic component of a large-scale long-life spaceconstructable heat pipe radiator.

The large vacuum chamber at JSC

was used to perform several experiments in a simulated tow-Earthorbit/ionospheric space plasma environment. Initial engineering verification tests were performed using a prototype Power Extension Package solar

array module in flight configuration.

The prototype PEP array was performance tested under conditions of solar

thermal vacuum and low-Earth-orbit

plasma, both separately and in combination, to fully explore and verify its

response under actual space operational conditions. The results verify

satisfactory performance under combined solar and plasma conditions

with plasma leakage current losses

less than 2 percent. Arcing to the

plasma was observed at voltages over

500 but was shown to cause no

damage to the array.

Advanced Onboard Propulsion

Technology

The advanced onboard propulsion

technology project will develop a candidate reusable onboard propulsion

system using nontoxic propellants for

future spacecraft. The fiscal year 1980

effort at JSC involved the characterization of nontoxic propellants and corresponding properties of ignition and

burn systems (thrust chambers,

nozzles, etc.).

Advanced Synthetic Aperture

Radar

The Advanced Synthetic Aperture

Radar project is designed to develop a

low-cost automated capability to perform active (radar) sensing in multifrequencies and multipolarizations for

multi-incidence angles. Such a

system would enable multimission execution at a substantial cost savings.

An antenna, a calibration technique,

and control logic for easy use by principal investigators to enable

multimode operations are the critical

technologies to be developed. The

goal is to develop an aircraft system

before developing a space capability.

Large Space Systems

Technology

A large space system technology program has been initiated to develop

techniques for space construction (fig.

3). These techniques include erection,

deployment, and automated fabrication methods.

Figure 3._Construction techniques.

Erection Fabrication Deployment
Automated fabrication is believed

to be a key requirement for a viable

program to construct large-scale

space systems. Some laboratory work

is underway to study such machines.

In addition to the fundamental construction techniques, numerous other

elements of construction systems are

being identified (fig. 4).

Large space systems technology

advances for fiscal year 1980 include

(1) designing and fabricating a fullscale functional model of a hexagonalframe/berthing-latch interface mechanism, and (2) forming and welding a

composite material (graphite-fiberreinforced thermoplastic) for space

structures.

The design requirements for the interface mechanism were derived from

an analysis of Orbiter constraints, platform interface requirements, and Orbiter Remote Manipulator System performance.

The graphite-fiber-reinforced thermoplastic has many desirable material

properties for application to space

structures. It has a high strength-toweight ratio and modulus of elasticity

and exhibits very little thermal distortion. Extensive modifications to an

existing bench test machine, which

includes use of heaters and coolers,

provided forming capability and commercial ultrasonic welding machines

joined the material.

Application of Advanced

Electric/Electronic Technology

to Commercial Aircraft

In fiscal year 1980, JSC conducted a

study to evaluate the potential of

designing an aircraft that would integrate the many subsystem technology

advances during the past decade, including those demonstrated in the Orbiter avionics system. These technologies include (1) redundant digital

fly-by-wire flight control and stability

augmentation, (2) computer management of vehicle systems, (3) electric

actuation for aircraft control surfaces,

(4) fiber optics communication and

data transmission, (5) laser gyros, and

(6) high-voltage electrical power

systems. The study concluded that an

all-electric secondary power system

on a wide-body advanced transport

aircraft fleet of 300 aircraft would save

S9 billion in direct operating costs over

a 16-year period. This conclusion supports further work by NASA in the

development of these technologies for

aircraft applications.

Figure 4._onstruction system elements.

Space construction _\_

jj

ane

icker

platform

Special tools

Tube fabrication

Automatic truss assembly

Beam fabrication

Automatic beam assembly

Work positioning fixtures

Strongback

Docking / berthing

ports

10
Office of Space

and Terrestrial

Applications

Summary

AgRISTARS Program

The Agriculture and Resources Inventory Surveys Through Aerospace

Remote Sensing (AgRISTARS) is a 6-

year program of research, development, evaluation, and application of

aerospace remote sensing for

agricultural resources beginning in fiscal year 1980. The program is a

cooperative effort of the U.S. Department of Agriculture (USDA), NASA, the

U.S. Department of Commerce, the

U.S. Department of Interior, and the

Agency for International Development.

The goal of the AgRISTARS Program is to determine the usefulness,

cost, and extent to which aerospace

remote-sensing data can be integrated into existing or future USDA

systems to improve the objectivity,

reliability, timeliness, and adequacy of

information required to carry out USDA

missions. The overall approach is

comprised of a balanced program of

remote-sensing research, development, and testing that addresses

domestic resource management as

well as commodity production information needs.

The program specifically addresses

the seven information requirements

identified in the USDA Secretary's

Initiative.'

1. Early warning of change affecting production and quality of commodities and renewable resources

2. Corr_modity production forecasts

3. Land use classification and

measurement

4. Renewable resources inventory

and assessment

5. Land productivity estimates

6. Conservation practices assessment

7. Pollution detection and impact

evaluation

While all seven are important to the

USDA, the first two--early warning

and commodity production forecasting--have been given emphasis

because of the immediateneed for

better and more timely information on

crop conditions and expected production.

The technical program is structured

into eight major projects, as follows.

1. Early Warning/Crop Condition

Assessment

2. Foreign Commodity Production

Forecasting

3. Yield Model Development

4. Supporting Research

5. Soil Moisture

6. Domestic Crops and Land Cover

7. Renewable Resources Inventory

8. Conservation and Pollution

These elements (fig. 1) are interrelated through research, exploratory experiments, pilot experiments, USDA

user evaluations, and large-scale application tests.

The Early Warning/Crop Condition

Assessment research effort is

designed to develop and test the

basic techniques required to support

the operational crop condition assessment division of the USDA's Foreign

Agricultural Service. This effort addresses 20 crop and region combinations in the United States and seven

foreign countries (U.S.S.R., Argentina,

Brazil, Canada, People's Republic of

China, Mexico, and Australia) for six

major commodities (wheat, barley,

corn, soybeans, rice, and cotton).2 The

techniques used for early warning are

assumed to be largely crop dependent

and country independent.

_Joint Program ol Research and Development ol Uses of Aerospace Technology for

Agricultural Programs, dated February 1978.

'These crops and regions may change in

response to USDA information needs.

Figure 1 ._omponent projects of AgRISTARS.

11
TheForeignCommodityProduction

Forecastingactivityaddresses12crop

andregioncombinationsintheUnited

Statesand six foreign countries

(U.S.S.R.,India,Argentina,Brazil,

Canada,andAustralia)forfivemajor

commodities(wheat,barley,corn,

soybeans, andrice).Thisprojectwilt

developandtestproceduresforusing

aerospaceremote-sensingtechnology

toprovidemoreobjective,timely,and

reliablecrop productionforecasts

severaltimes duringthe growing

seasonandimprovedpreharvest estimatesforthecropsandregionsofinterest.TheForeignCommodityProductionForecastingactivitybuilds

uponthe existingremote-sensing

technologybaseand extendsthis

technologyto additionalcropsand

regions.Large-scaleapplicationstestingof candidatetechnologyformakingestimatesof productioninforeign

countrieswill be conductedby the

USDA.

TheYieldModelDevelopment will

support USDAcrop production

forecastingandestimationby(1)testing, evaluating,and selectingcrop

yieldmodelsfor applicationtesting;

(2) identifyingareasof feasible

researchfor improvement of model

usefulness;and (3) conducting

researchto modifyexistingmodels

andtodevelopnewcropyieldassessmentmethods.

TheSupportingResearchproject

coversresearch,development,and

testingof newandimprovedremotesensingtechnology. Researchwill be

conductedin thefollowingareasas

relatedto applicationsof remotesensingtechnology: areaestimation,

cropdevelopmentstageestimation,

spectralcrop appearancein yield

estimation, cropstress,andsoils.

The Soil Moistureresearchis

directedtowarddevelopment of the

measurement ofsoilmoisture(insitu

andremotely)forpotentialuseinother

applications,suchas earlywarning,

crop yield estimation,watershed

runoff,andvegetativestressassessments.

The DomesticCropsand Land

Coverobjectivesaredirectedatautomaticclassificationandestimationof

landcoverwithemphasison major

crops.Landsatandadvancedsensor

datawillbeusedinconjunctionwith

grounddatato improvetheprecision

of estimationandclassificationproceduresatthesubstatelevelandtoinvestigatechange-monitoringtechniques.

TheRenewableResourcesInventory projectinvolvesrequirementsin

sevenmajorproblemareas:regional

and large-areainventories;current

technologyassessment; new technology development;detection,

classification,and measurement of

disturbances; classification, modeling,

and measurementof renewable

resources;determinationof site

suitabilityandlandmanagement planning;andanalyticalandcartographic

supporto the resourceinformation

displaysystem.

Theconservationassessment portionof theConservationadPollution

projectaddressesapplicationsin

threeareas:inventoryofconservation

practices;estimationof waterrunoff

usinghydrologicmodels;anddeterminationofphysicalcharacteristicsof

snowpacks.Thepollutionportionof

theprojectwillprovideanassessment

ofconservationpracticesthroughuse

of remote-sensingtechniquesto

quantitativelyassessedimentrunoff,

todetectgaseousandparticulateair

pollutants, andtoassesstheirimpact

onagriculturalndforestryresources.

Forest Resource Information

System

The prime goal of this project is to

determine the viability of using

satellite remote-sensing technology

for industrial forest management applications in the Southeastern United

States. It is a 3-year cooperative project between the Southern Timberlands Division of the St. Regis Paper

Company, the Laboratory for Applications of Remote Sensing of Purdue

University and the Johnson Space

Center (JSC). The project represents

the first private sector (wood products

industry) user in NASA's Earth

resources programs and is significant

since the user also shares in the management and cost responsibilities for

the implementation of the Forest

Resource Information System. JSC is

primarily responsible for the contractual support with the Laboratory for Applications of Remote Sensing in

developing specified quantifiable

forest resource information from Landsat multispectral-scanner data and

correlating this information with St.

Regis-furnished inventory data on

specific test sites. The contractor will

develop the software and classification analysis procedures and provide

for the technical training of St. Regis

personnel. This project also calls for

the establishment of a Forest

Resource Information System design

and implementation based on the

project results and, finally, documentation of these results for release to the

public domain.

12
Wildland Vegetation Resource

Inventory

A Wildland Vegetation Resource Inventory Application Pilot Test is being

jointly undertaken by the Bureau of

Land Management of the Department

of the Interior and JSC to test and implement an interactive system to

assist in the inventory of public lands.

This test is presently in the third and

final phase. Each phase--Alaska,

Arizona, and Idaho--was related to a

different ecological zone; the sites

were carefully selected to represent

the varied lands under the management of the Bureau of Land Management. The Alaska phase, which began

in May 1977 and was successfully

completed in July 1978, was primarily

a land-cover inventory of approximately 2.5 million acres in South

Central Alaska. The Arizona phase,

October 1978 through June 1980, not

only used the experience and

knowledge gained in the Alaska project but went one step further by

developing productivity estimates for

range forage (pounds per acre) and

forest and woodland volume (cubic

feet per acre) by type. The Bureau of

Land Management tested the

knowledge gained during the project

by doing an independent land-cover

classification of the Arizona Test Site.

The Bureau of Land Management is

presently conducting a project over

the Idaho Test Site using all the

capabilities learned during the other

two phases of the Application Pilot

Test. The NASA contractor is completing project documentation and transfer

of the technology to the Bureau of

Land Management with the Application Pilot Test scheduled for completion in March 1981.

Texas Application System

Verification and Transfer

The JSC is participating with the State

of Texas in a joint Application System

Verification and Transfer Project to

develop, evaluate, and transfer techniques for applying Landsat and other

data to the needs of Texas natural

resources management agencies. The

major objectives of the project are (1)

to update and integrate state-of-theart remote-sensing technology with

other information sources available to

the State to form a functional Texas

Natural Resources Inventory and

Monitoring System, and (2) to test and

evaluate the utility and cost-effectiveness of natural resource information

derived from Landsat data and other

sources when applied in a total system

context to selected State agency management activities. The Texas Applications Project began in June 1978

and spans 3 years.

The remote-sensing component of

the system is NASA's major responsibility. A prototype of the system will

be operational on Texas facilities in

late 1980. The system is being tested

and evaluated in support of application categories in the areas of coastal

zone management, forestry, water

resources, mineral resources, and

wildlife management.

13

Office

of Space

Sciences

Summary

Lunar and Planetary Sciences

During fiscal year 1980, planetary

sciences came of age at the Johnson

Space Center (JSC) as evidenced by

the broad range of experimental and

theoretical investigations currently

being pursued. Sample-oriented

research on lunar and meteorite

materials continues to be the major

activity of JSC scientists. New and

continued studies of Mars, Venus, and

the Galilean satellites of Jupiter demonstrate involvement in up-to-date

planetary research. The consolidation

of research on the ancient crust of the

Earth has been gratifying as such

research will form a solid base for

planetary research during the decade

of the 1980's.

The activities of JSC in lunar and

planetary sciences that are summarized in the following paragraphs

include lunar studies, meteorite

studies, Earth's ancient crust, Mars,

Venus, cosmic dust, comets, Galilean

satellites, cratering, and technology.

Lunar Studies

As research in Lunar and Planetary

Sciences diversifies, the fraction of

total effort devoted to lunar studies

continues to decrease and now accounts for about one-third of the total;

but there are three investigations that

demand special mention.

A study of the relative composition

of the elements samarium, titanium,

and scandium in lunar plutonic rocks

found that the processes that are

responsible for the formation of the

lunar crust were strongly constrained.

This work demonstrated that

anorthosites did not experience a previous ilmenite fractionation whereas

norites and troctolites did. Conversely,

all plutonic rocks experienced some

previous pyroxene fractionation,

although this effect is more important

for the norites and troctolites than it is

for the anorthosites.

The rocks that form the lunar crust

are widely believed to have formed

from an outer shell of liquid rock

several hundred kilometers thick early

in lunar history. A problem is how to

account for the compositions of the

observed rocks if the liquid shell,

called a magma ocean, has a composition like the bulk Moon. A study of

the effects of impact showed that the

impacts that account for the accretion

of the Moon were of relatively low

velocity and as such could not produce

impact melts. However, impact melts

are melts with compositions of the

bulk Moon. What low velocity impacts

can produce is general heating which,

in excess, will produce partial melting.

A magma ocean formed by partial

melting will be basaltic, and not of

bulk Moon composition. This idea

simplifies the problem of accounting

for the compositions of the observed

rocks.

One of the most important Apollo

experiments was the X-ray map of a

portion of the Moon obtained during

Apollo 15 and 16. However, the usefulness of that data has been very limited

because of the low spatial resolution.

One scientist, in a new effort using image-enhancement techniques, has

improved the spatial resolution of the

X-ray data by a factor of two (fig. 1).

This advance should provide the grist

for many interpretative investigations.

Meteorite Studies

The JSC continues to be involved in

the collection and curation of Antarctic

meteorites in association with the National Science Foundation and the

Smithsonian Institute. The meteorites

are proving to be a vast storehouse of

secrets concerning the solar system.

The early examination of the

meteorites in the meteorite laboratory

is yielding important new data concerning meteorite populations.

Figure 1 .--An example of a portion of the X-ray map for the Moon revealing the improved resolution and contrast o! geochemical "pictures." The two views illustrate the power of the new JSC

image enhancement technique. The improvement in spatial resolution is obvious by inspection

of the two images generated by a computer printer. The density of the regions represent

differences in the ratio of magnesium to aluminum on the surface of the Moon.

Original

Southeast Mare Serenitatis

Enhanced

By Laplacian Subtraction

15
Researchon Antarcticand other

meteoritescoversa rangeof descriptive topics.A particularlyimportant

resultinvolvesthe discoveryof a

youngage for severalachondritic

meteorites.

Earth'sAncientCrust

RecognitionthattheEarthisa planet

thatisaccessibletodetailedstudyhas

directedsignificanteffortto usethe

Earthasamodelforthegeneral planetaryprocessof crustalformation. JSC

effortshavebeendirectedtowardthe

originanddevelopment oftheEarth's

continentalcrust.Severalparallel

studiesarebeingfollowedinthedisciplinesof geochemistry, petrology,

geochronology, andfieldgeology.One

projectconsistsof systematically

locatinganddocumentingtheoldest

rocksinNorthAmerica.Rocksasold

as3700millionyearshavebeenfound

inMinnesotaandrocksasoldas3200

millionyearshavebeendiscoveredin

Ontario,Wyoming,and Montana,

althoughmuchofthisancientterrainis

only2800millionyearsold (fig.2).

Bothpetrographyand geochemistry

arebeingperformedontheseancient

rocks.

Ancientanorthositesfrom Minnesota and Ontario are being

investigatedas a modelfor the

basalticgrowthof continents.Recent

workhasdemonstratedthatancient

anorthositecomplexesarechemically

richer in aluminumthan younger

anorthositiccomplexes.

Theoretical studiesareattempting

to integratethe knowledgegained

directlyfromtheMoonandapplyit to

thestudyof theEarth.Modelshave

beengeneratedthatdemonstratehow

anEarthmagmaoceanwouldwork

andwhattypeof crustit wouldproduce.Thepossibleexistenceof an

Earth magma ocean is being

investigatedbya worldwidestudyof

theoldestrocksonEarth.

Mars

There are several studies underway to

learn about weathering on Mars. One

study uses soil core tubes collected

from the dry valleys in the Antarctic

because those valleys are candidate

analog environments to the cold dry

conditions on Mars. A second experimental study uses a Mars weathering

simulation chamber. The chamber experiments demonstrate that Mars is

heated by sunlight and that the heating causes Mars to be red.

Venus

Venus is Earth's twin in size and density, but its surface is very different.

The Venusian atmosphere is very hot

(500 ° C) and consists of carbon dioxide with small amounts of sulfuric acid.

A study to understand the surface environment has been performed and a

model has been produced that suggests that the bottom of the Earth's

oceans is a good analog to the surface

of Venus. The model suggests that the

very level surface of Venus (fig. 3) is

due to windblown sediments and that

the material in the level part of Venus

is transported from the few plateau

regions.

Cosmic Dust

JSC is pursuing a twofold thrust involving the collection and population

analysis of cosmic dust. Population

analysis flows from data collected on

the Pioneer 10 and 11 spacecraft; new

data will be obtained from the Galileo

spacecraft. Collection studies are

Figure 2._sochron diagram for some ancient crustal rocks discovered inthe Beartooth Mountainsof Montanaand Wyoming.This

diagram showsthat approximately50 analyzed rocks fall on a line

that yields an age of 2780 millionyears. Theplot is based on theRbSrradioactive decay system.87Rbdecays to 87Srand 86Sris usedas

a normalizationparameter, As a system ages, the line defined by the

analyzedpoints rotates counterclockwise. The steeper the line,the

older the rock system.

0,78

0.74

0.70

0

87Sr / 86Sr "Jl' _

2780 $ 25 M.Y,

0.7022 _'Z-2

_" 87Rb / 86Sr

I J I I

10 2.0

16

Figure &--Plot demonstrating the differences inthe surfacetopography of Earth and Venus. This diagramshows that 60 percent of the

Venusian surface has an elevation within0.5 kilometer of the mean

elevation.By contrast,Earthdisplaysa muchwider rangeof surface

elevations.Thetwo peaks on theEarthcurverepresenttypical continental elevation and typical ocean bottom elevation.

60

so VENUS

_- -8 -6 °4 -2 0 2 4 6

ELEVATION
based on spacecraft and airplane

flights. The spacecraft experiment will

consist of a cosmic dust collector on

the Long Duration Exposure Facility

that will remain in Earth orbit for over 1

year. The aircraft program consists of

collecting cosmic dust on high-flying

JSC aircraft. The collectors for the

aircraft program are being fabricated

and the first collection will be made in

fiscal year 1981. Expectations are that

much new and important data will be

obtained from these collected

materials.

Comets

One of the most exciting activities during 1980 was formally proposing two

flight instruments for NASA's proposed

mission to Comet Halley and

Tempel-2. Both instruments were

designed to collect comet dust and

perform geochemical analysis on that

dust. One instrument, the scanning

electron microscope, analyzes individual dust particles for particle

morphology and size and analyzes

major elements and organic molecule

content. The other instrument

analyzes a bulk sample of comet dust

for trace elements and isotopic composition and obtains an age for the

comet (fig. 4).

Galilean Satellites

A new project was initiated in 1980 to

study the global tectonics of

Ganymede, the largest satellite of

Jupiter. The contrasting dark and light

cratered grooved portions of

Ganymede are being interpreted as

being in plate-tectonic relation to

each other. The dark portions of

Ganymede drift relative to each other

and the light portion is a filler between

the dark plates. A theoretical study

was also performed to investigate the

internal mineralogy of Io, the volcanic

satellite of Jupiter. This study is based

on a calculated phase diagram for the

system iron-sulfur-oxygen. Voyager

results prompted both of these

studies.

Cratering

Cratering studies, which receive a

continuing strong emphasis, have

resulted in the publication of a major

new model for the mechanics of crater

formation as a function of the impacting projectile's composition and

velocity and target composition and

volatile content. This model was used

to predict the effects of cratering on

icy planets.

Technology

A major technology effort to improve

the curation of Moon rocks and

meteorites was completed with the

opening and operation of the Lunar

Curatorial Facility. Technology efforts

also continue in a range of analytical

endeavors. Fiscal year 1980 marked

the first direct dating of an anorthosite.

(The Adirondack Anorthosite is 1200

million years old,) Image enhancement of lunar X-ray data and new instrumentation for flight experiments

have been mentioned previously.

Life Sciences

The Medical Sciences Division of the

Space and Life Sciences Directorate

at JSC conducts a broad range of

medical research and operations activities in support of the goals of the

Office of Space Science. The basic

objective of these activities is to

assure the health and safety of all

those who fly in space. In pursuing this

objective, every effort is made to increase man's knowledge of the medical sciences and to apply this

knowledge to the solution of man's

problems on Earth as well as in space.

Research areas of significance to

manned space flight include neurophysiology (space motion sickness),

cardiovascular physiology, bone and

muscle metabolism, endocrinology,

and microbiology. The technology

developed in carrying out investigations in these areas has resulted in

several significant advancements in

medical research during the past year.

An area of research of considerable

importance to the Space Shuttle Program is that of space motion sickness.

Although less than half of all those

who have flown in space have shown

any symptom of space motion sickness, this illness can incapacitate an

affected crewman for several days.

Thus, it is important that all avenues of

research be explored thoroughly to

assure that every step is taken to understand the cause, the effect, and the

treatment of this space-associated

Figure 4.--Assembly diagram for the mass spectrometry isotope dilution experiment that JSC

proposed for the Comet Halley/'rempel 2 mission. The sample collection assembly has a funnel

to aid in collection of comet dust by concentration, The collected dust would be chemically

processed using the dissolution and carrier acids with the excess acid being deposited in the

excess-acid sink. The processed sample would be deposited on a filament in the mass

spectrometer source chamber and analyzed by the mass spectrometer.

) PROCESSOR

ELECTRONICS

DISSOLUTION ACID RESERVOIR

NEUTRALIZER AND TRAP

ESS ACID SINK

SAMPLE

COLLECTION ASSY.

GN 2 TANK

CARRIER ACID RESERVOIR

MASS SPECTROMETER

MASS SPECTROMETER

SOURCE CHAMBER

DATA SYSTEM

ELECTRONICS

POWER SUPPLY

17
syndromeIt is widelyacceptedthat

alterationsof theotolithreceptorsof

theinnerearareprimarilyresponsible

forthevestibulardisturbancethatis

characterizedbythesymptomsofmotion sicknessin space.Linearaccelerationisoneof theveryeffective

stimuliusedto inducea responsein

the otolithreceptors.To studythe

otolithreceptorand its responseto

controlledchanges,a linearaccelerator designedto carryonemanwas

developedby NASAin conjunction

withtheUniversityofMichigan.

Aparticularlypromisingapplication

ofNASAtechnologyistheutilizationof

the multiwireproportional counting

techniquein medicalimagingof cardiovascular performance. Thisdevice

providesaseriesofpicturesproduced

byinjectingashort-livedradioisotope

intothebloodstreamandcountingthe

radioactive particles given off as the

isotope moves through the heart.

Figure 5 shows a cardiac phantom

with the image processed to display

edge contour. The image was obtained with the phantom at diastole

(140 milliliter volume) using a tantalum-178 tracer. This system can obtain measurements for determination

of stroke volume, ventricular ejection

fraction, and heart chamber wall

movements that have significant diagnostic value in cardiology.

Over the past several years, NASA

and the Baytor College of Medicine

have cooperated in the development,

testing, and use of a mobile biological

isolation system. This system was

developed for use by a young child

afflicted with a severe immunization

deficiency. During the past year, additional efforts have been made to improve this system.

The JSC Engineering and Development Directorate and the Space and

Life Sciences Directorate cooperated

with the Stehlin Foundation for Cancer

Research in the development of improved radiofrequency heating techniques for the treatment of certain

types of cancer. This project utilized

NASA technology and expertise to

develop a system for experimental

treatment of small animals. This

system was the prototype for a second

system that was developed and used

in the treatment of certain tumors in

h u man patients.

Figure 5.---Cardiac phantom with image processed to display edge contour.

18
Significant

Tasks

Office of Space

Transportation

Systems

Significant Tasks

23 Space Operations Center System Analysis

Funded by: Major Systems Studies (UPN-906)

Technical Monitor: S. H. Nassiff/EB

Task Performed by: Boeing Aerospace Company

Contract NAS 9-16151

Rockwell International

Contract NAS 9-16153

24 Power Extension Package Power Conditioning Evaluation

Funded by: Advanced Development (UPN-906)

Technical Monitor: W. C. Stagg/EH5

Task Performed by: Lockheed Engineering and Management

Services Company, Inc.

Contract NAS 9-15800

25 Manned Remote Work Station Development

Funded by: Advanced Development (UPN-906)

Technical Monitor: S. H. Nassiff/EB

Task Performed by: Grumman Aerospace Corporation

Contract NAS 9-15881

26 Maneuverable Television

Funded by: Advanced Development (UPN-906)

Technical Monitor: R. H. Gertach/ED4

Task Performed by: Lockheed Engineering and Management

Services Company, Inc.

Contract NAS 9-15800

27 Advanced Extravehicular Crewman Work System

Funded by: Advanced Development (UPN-906)

Technical Monitor: M. RodriquezlEC2

Task Performed by: Hamilton Standard Division

Contract NAS 9-15290

28 Satellite Population Assessment

Funded by: Advanced Development (UPN-906)

Technical Monitor: D. J. Kessler/SN3

Task Performed by: Lockheed Engineering and Management

Services Company, Inc.

Contract NAS 9-15800

Analytical Computational Mathematics Inc.

Contract NAS 9-15883

Western Electric Co., Inc.

Contract NAS 9-16127

21
30

31

32

33

34

35

36

Solid Polymer Electrolyte Fuel Ceil

Funded by: Advanced Development (UPN-906)

Technical Monitor: D. Bell III/EP5

Task Performed by: General Electric Company, DECP

Contract NAS 9-15286

Space Construction Experiments Concepts

Funded by: Major Systems Studies (UPN-906)

Technical Monitor: L. M Jenkins/EB

Task Performed by: Rockwell International

Contract NAS 9-15718

Space Construction System Analysis

Funded by: Major Systems Studies (UPN-906)

Technical Monitor: S. H. Nassiff/EB

Task Performed by: Rockwell International

Contract NAS 9-15881

Loads and Dynamics of Variable-Geometry Structures

Funded by: Advanced Development (UPN-906)

Technical Monitor: John Schliesing/ES2

Task Performed by: Grumman Aerospace Corporation

Contract NAS 9-15895

Manned Geosynchronous Mission Requirements and Systems

Analysis

Funded by: Major Systems Studies (UPN-906)

Technical Monitor: H. G. Patterson/EB

Task Performed by: Grumman Aerospace Corporation

Contract NAS 9-15779

Fiber Optics Multiplexing

Funded by: Advanced Development (UPN-906)

Technical Monitor: E. A. Dalke/EH42

Task Performed by: McDonnell Douglas Astronautics Company

Contract NAS 9-15585

High-Power Traveling-Wave-Tube Amplifier

Funded by: Advanced Development (UPN-906)

Technical Monitor: B. Kilker/EE3

Task Performed by: Hughes Aircraft Company

Contract NAS 9-15235

22
Space Operations Center

System Analysis Study

The Space Shuttle will be the primary

mode of space transportation for the

next decade and will serve as the initial space base or platform for a number of planned missions of relatively

short duration. However, many mission

payload concepts now being proposed

and under study will require operational support capabilities beyond

those of the Space Shuttle. Future

planned programs and projects indicate a need to deploy, assemble, and

construct large systems in space and

to support long-duration missions for

science and applications, satellite

servicing, technology development,

and flight support for orbit transfer

spacecraft. Additionally, a larger

multiskilled crew will be required with

the necessary habitability provisions

and with provisions for increases in

electrical power, communications,

multidocking or berthing, propellant

storage and transfer, and construction

and manipulator equipment. A facility

such as the Space Operations Center

(SOC) is needed to provide these

operational capabilities to accomplish

current and future planned programs

and projects.

The Space Operations Center system

analysis performed by Boeing Aerospace Company will include identification of a mission model and

requirements for facilities for construction, flight support, and satellite servicing. An overall system analysis will

be performed that will include technology assessment for the SOC program. Rockwell International will

analyze SOC/Shuttle interaction and

will address the issues of Orbiter

docking or berthing with SOC, SOC

assembly and buildup, resupply and

propellant transfer, and more

specifically, SOC flight support facility

requirements. A SOC assembly and

buildup is shown in figure 1.

The output of the SOC/Shuttle interaction effort will be an input to the overall

study of the SOC concept which has

been underway in-house at Johnson

Space Center for the past several

years. Emphasis will be placed on the

identification of constraints imposed

by the Space Shuttle in its interaction

with the SOC and on design or technical solutions that will allow satisfactory

accomplishment of the interactions.

The overall system analysis study will

then provide SOC system requirements, system description, system

analysis results, and a technology

assessment and advancement plan

that will be used in future development activities.

Figure 1..--.FinalSOC configuration.

23
Power Extension Package

Power Conditioning Evaluation

A highly critical element in the Power

Extension Package (PEP) (fig. 1)

system design is the choice of the

power conditioner or voltage regulator

used to convert the unregulated high

voltage (130 to 170 V dc) at the output

of the PEP solar array to regulated low

voltage (30 V dc) for the Orbiter

electrical power system. The conversion efficiency and peak-power-tracking efficiency of the regulator design

are important because both affect the

size, and consequently the cost, of the

PEP solar array required to deliver 26

kilowatts electrical power to the Orbiter at the array end-of-life. Conversion efficiency is also important

because it determines the heat load

imposed on the Orbiter thermal control

system by the regulators. Other factors

that are critical are the overall system

operating stability, the ripple produced, and the transient response

when the regulators are supplying the

Orbiter electrical buses in parallel with

the Orbiter fuel cells. Early attempts to

gather regulator performance data on

which to base PEP regulator selection

proved futile because of the immature

development status of suitable regulators and the unique nature of the PEP

application.

A study was initiated at JSC in April

1978 that had multifold purposes: (1)

to conduct an industry-wide survey to

determine predicted performance

parameters for a number of regulators

in various stages of development, (2)

to select three or four of the most promising design approaches and obtain

breadboard models for detailed

evaluation testing in the Shuttle/Orbiter Electrical Power Distribution and Control (EPDC) breadboard

(fig. 2) at JSC (the only high-fidelity

simulation of the entire Shuttle/Orbiter

electrical power system in existence),

and (3) to select one or more successful models for further testing with

an actual Orbiter fuel cell to validate

the breadboard test results and to investigate fuel cell performance in the

PEP operating mode. Following completion of the industry survey, four candidate regulator designs were chosen

for testing in the EPDC breadboard: (1)

a McDonnell-Douglas buck regulator,

(2) a NASA Marshall Space Flight

Center programmable power processor (p3) (buck regulator), (3) a

Lockheed Missiles and Space Company transformer-coupled converter,

and (4) a series resonant converter

from Wright-Patterson Air Force Base

modified for the PEP application. A

simulated single-string PEP was

added to the Orbiter EPDC breadboard, including a high-fidelity solar

array simulator, high- and low-voltage

distribution wiring, and high-power

switching contactors and fusing. Test

plans and procedures were developed

and testing began in August 1979. The

parameters evaluated included conversion and peak-power-tracking efficiencies; input and output ripple;

response to a variety of load transients; regulator and fuel cell load

sharing at various regulator output

voltage set points; and overvoltage,

overload, and short circuit fault protection techniques.

To date, three of the four regulators

have been tested in the EPDC breadboard with results that tend to verify

earlier predictions of PEP performance. Buck-type as well as

transformer-coupled converters/

regulators have been demonstrated to

operate with conversion efficiencies

as high as 92 percent and peakpower-tracking efficiencies as high as

99 to 99.5 percent. Load sharing between the regulators and the fuel cell

simulator has been as expected and

varies with regulator voltage as predicted. Final verification of these

results is expected to be achieved

through actual fuel cell tests during

early 1981.

Figure 1.--Orbiter Power Extension

Package. Figure2.---Power ExtensionPackage power conditioningsystembreadboard.

. i

24
Manned Remote Work Station

Development

A prime Space Shuttle requirement is

that the Shuttle will have the

capability to service the satellites that

are attached in the payload bay and

detached in a free-flying mode.

Studies have identified the specific

hardware development necessary for

the extravehicular activity (EVA) astronaut to increase orbital productivity for

satellite servicing and maintenance,

inspection, and repair of the Orbiter.

One identified need is to provide the

astronaut with a stable platform from

which he can perform a variety of work

functions coupled with the capability

to transport replacement modules to

and from the Orbiter. The manned

remote work station "open cherrypicker" (OCP) is a versatile system

that can provide these capabilities.

The cherrypicker is attached to the

end of the Orbiter Remote Manipulator

System (RMS) and the RMS and OCP

are controlled and operated by an EVA

astronaut located on the OCP work

platform. The cherrypicker will not

only enhance Space Shuttle operations in the near term for satellite servicing, but it will also provide the

capability to demonstrate early onorbit

construction techniques and operations that can be used to optimize construction of future large-system projects.

A program that includes flightqualified basic OCP structure and

development test article components

and mechanisms has been formulated

for early OCP flight demonstration.

This approach includes engineering

simulations, environmental testing,

water immersion facility (WlF) tests,

ground and flight tests, and hardware

development and cost for a flight article available by 1985. A simulation

program has been developed and is

currently underway to perform OCP

systems evaluation and to demonstrate satellite servicing using a sixdegree-of-freedom simulator. The

open cherrypicker is shown servicing

a satellite attached to the Orbiter

payload bay in figure 1.

Two full-scale OCP development test

articles (DTA's) have been built. One

has been used in recent water immersion facility testing at JSC to evaluate

system components and operation.

The other OCP is located at Grumman

Aerospace Corporation on the sixdegree-of-freedom simulator. Additional WlF tests are planned to evaluate the cherrypicker subsystems and

to demonstrate satellite servicing. The

OCP DTA will be integrated with the

JSC Manipulator Development Facility

in mid-1981 and used in simulations

on the end of the RMS arm while both

are supported on an air-bearing floor

(fig. 2). Future applications of the

manned remote work station include

closed pressurized cabin versions,

railed work stations, and free-flying

work stations.

Figure 1 .-_Open cherrypicker simulation.

Figure 2.--The manipulator development facility and the open cherrypicker on the air-bearing floor.

25
Maneuverable Television

The Space Shuttle mission model includes many payload deployment and

retrieval operations to support satellite

servicing. Many payloads will require

inspection and may require maneuvering assistance during deployment and

retrieval. The Maneuverable Television

(MTV) (fig. 1) is a versatile subsatellite

to support the satellite services requirements for the Orbiter by providing

this remote capability.

A study was initiated in fiscal year

1978 to define an inspection and

documentation device that could extend the remote television viewing

capability of onorbit cameras attached

to the Orbiter vehicle and to the

remote manipulator. The effort identified a maneuverable television concept for a subsatellite that will free-fly

in the vicinity of the Orbiter. This

television is remotely controlled by the

crew of the Orbiter and is directed by a

crewman to fly to the desired inspection point. The maneuverable television is approximately 1 meter on each

side and is berthed in the payload bay

of the Orbiter. Docking and undocking

is remotely controlled and real-time

transmission is provided to the crew

during flight. An in-house JSC program

was initiated in fiscal year 1980 to

define and develop an engineering

model of the MTV to demonstrate

feasibility.

The subsystems of the vehicle were

identified and designed using primarily off-the-shelf equipment. The

components and parts have been

fabricated at JSC and the electronic

boxes have been obtained. A flight

control system computer model has

been developed for analysis. The fullscale chassis has been assembled

and the subsystem components are

being installed. The full-scale

engineering model will be completed

in fiscal year 1981. The model will be

operated on the air-bearing facility at

JSC.

Figure 1 .--The Maneuverable Television.

ATTITUDE

REFERENCE

HORIZON

SENSORS,

PROPULSION

TANKS

ELECTRONICS

ASSEMBLY

BATTERIE: JPLERS

ANTENNAS

RADAR

(RANGE RATE)

TV LIGHTS

TV CAMERAS

CONTROL

ASSEMBLY

DOCKING

INTERFACE(3)

26
Advanced Extravehicular

Crewman Work System

As the Space Shuttle Program

matures, a "next generation" extravehicular activity (EVA) work

system will be required to support advanced activities such as satellite

servicing and long-range missions

such as the Space Operations Center.

Satellite servicing will necessitate a

sophisticated EVA system that not

only allows the crewman to perform

the required activities but also incorporates high-technology diagnostic

equipment for fault isolation. To properly support typical Space Operations

Center activities, there is a need to

improve the existing EVA technology

base so that routine low-overhead

long-duration noncontaminating EVA's

can be conducted.

The advanced Extravehicular Crewman Work System study was initiated

to explore the additional requirements

imposed by the new Space Transportation System (STS) operations inherent in the NASA 5-year plan. The

study, which was completed in July

1980, was to generate an Extravehicular Mobility Unit (EMU) development/growth plan to coincide with the

projected development of the STS.

The results indicate a need for a

phased development initially aiming

at satellite servicing and gradually

evolving into the development of the

subsystems required for EVA operations in high-energy orbits.

Figure 1 .---Enhanced capability extravehicular activity equipment.

DEPLOYED RADIATOR-AUXILIARY

PANELS ADJUSTABLE FOR

MAXIMUM

LIGHTS

CAMERA

LIGHT

TRANSMISSION VISOR

;TOVEPIPE JOINT

CONTROLS

TEMPERATURE

SENSOR--

HIGH-TACTILITY

GLOVES

SPOTLIGHT

TEGRAL TOOL

ADAPTER

ADDITIONAL CAPABILITIES:

• NO VENT-REGENERABLE HEAT SINK

• NO PRE-BREATHE REQUIRED

Promising EMU design improvements

include (1) liquid absorbent for carbon

dioxide that is regenerated electrochemically in the spacecraft, (2) a

thermal control concept using a radiator on the rear surface of the portable

life support system (fig. 1) as part of a

simple vapor compression refrigeration cycle to reject heat, (3) lithium

thionyt chloride or sulfuryl chloride

batteries for increased energy density

and recharge capability, and (4) advanced microprocessor techniques for

controlling supply and demand by adjusting ventilation and water controls

to the crewman and to the refrigeration

compressor.

For the space suit assembly, candidate concepts include (1) an electronic transparency control for the visor

areas to provide automatic peripheral

sunshades and glare protection, (2)

the application of magnetic-pulseforming technology to improve the integrity of fabric-to-metal space suit attachments, (3) use of single-piece

toroidal mobility joints based on heatshrinking a combination bladder/

restraint layup on a master mandrel to

eliminate the reliance on costly sewn

seam construction, (4) use of a triaxial

fabric to provide better load distribution and avoid fabric distortion, (5) improved shoulder joint using truncated

or "stovepipe" surfaces, and (6) an integrated glove/tool end adapter to provide a powered tool assembly universally adaptable to a variety of applications.

27
Satellite Population Assessment

As the number of artificial satellites orbiting the Earth continues to increase,

the possibility that they may interfere

with future operations in space also increases. Research is being conducted

to identify potential hazards, evaluate

alternatives, and recommend policy

changes as necessary. The analysis to

date has identified three areas of concern: the hazards from the tracked

population, from the untracked population, and from the future population.

These concerns are identified for both

low Earth orbit (less than 2000

kilometers) and geosynchronous orbit.

Tracked Population

The NORAD is currently tracking approximately 4700 objects in space.

Most of them appear to be larger than

about 10 centimeters in diameter, in

low Earth orbit, and to originate from

explosions either from U.S. spent

stages or from U.S.S.R. antisatellite

tests (table I). The observed growth

has been between 10 and 13 percent/yr with the greatest concentration

between 500 and 1100 kilometers.

The probability of collision for a 50-

meter-radius spacecraft is calculated

to be O.O05/yr at 500 kilometers and

O.01/yr at 1100 kilometers. For geosynchronous altitudes, the calculated

probabilities are between 1 x 10 -5

and 1 x l O-4/yr. However, only objects larger than approximately 1

meter in diameter are detected at this

altitude.

Untracked Population

Knowledge that an untracked population exists follows from two principal

sources: (1) that the more than 50 explosions in space would have been

expected to have produced many objects too small to be tracked and (2)

that objects that appear to be as small

as 4 centimeters in diameter are frequently detected by NORAD radar just

prior to reentry. Objects of this size are

sufficiently energetic in low Earth orbit

that, at their average relative velocity

of 10 km/s, they would penetrate approximately 20 centimeters of solid

aluminum upon collision. Based on the

observed number of these objects at

400 kilometers and on the size distributions that could be expected from

low-intensity explosions, collision

probabilities can be estimated. The

probability of collision for a 50-meter

radius spacecraft with the 4-centimeter and larger population is estimated to be 0.01/yr at 500 kilometers

and O.05/yr at 1100 kilometers. These

probabilities are surely higher for

smaller debris but insufficient data exist to make a reasonably accurate estimate. At geosynchronous altitude, the

population to 4 centimeters may be

approximately a factor of 10 larger

than the observed population, leading

to an estimated collision probability

between 0.0001 and 0.001/yr.

TABLE I.-- SOURCE OF IN-ORBIT POPULATION TRACKED BY NORAD

SPACE OBJECT PERCENTAGE OF TRACKED NOTES

POPULATION IN ORBIT

Operational payloads 5 Distributions are roughly equally divided between the UrS S R. and the

United States.

12

18

54

Nonoperational payloads

Mission related (rocket

bodies, shrouds, etc)

Explosion fragments

To-be-determined origin 11

6 Delta stages 20 percent '}

3 Agenas 12 percent / United States 2 other 10 percent 42 percent

8 U.S,S.R. satellite tests 12 percent

Whereas a certain fraction of these objects may prove to be nonexistent,

most are probably explosion fragments, Many will reenter before they

become part ol the official catalogue. Some are in geosynchronous orbit

and are possibly refound obiects with orbits that are no longer maintained.

28
FuturePopulation

Ifpasttrendscontinue,thenumberof

objectsin spacecanbeexpectedto

doubletoquadruplewithinthenext20

years,thus increasingthe previous

probabilities by a corresponding

amount.However,moreimportantly,

theremaybea sufficientnumberof

objectsinspacethatseveralcollisions

could be expectedbetweennonoperational objectsin towEarthorbit

(fig.1).Theconsequencesofonlyone

of thesecollisionswouldbe to producea distributionof fragmentsthat

includes1.4 x 104particleslarger

than1centimeterand3.5x 106particleslargerthan1millimeter.A1-centimeterobjectinlowEarthorbitwould

penetratea5-centimeterthicknessof

solidaluminum. Thecollisionfrequency ona 50-meterspacecraftwiththe

1-centimeterpopulationin the year

2000couldbe about0.1tyrat 500

kilometers and l/yr at 1100

kilometers.The largernumberof

smallerfragmentscouldsignificantly

affectthereliabilityof muchsmaller

structures. Inaddition,thishigh-collisionfrequencycouldbeginacascading effect, further increasingthe

populationgrowthof fragmentsand

leadingtoanonreversiblefragmenting

process.

A computermodelto accurately

definetheseissuesis approximately

50 percentcomplete.Theresultsto

date tend to confirm previous

preliminaryanalyses.This model,

when completed, will predict

spacecraftlifetimesfrom collisions

andwillevaluatetheeffectivenessof

variouscontroloptions.Theseoptions

includetheretrievaloflargenonoperationalobjects,theplannedearlyreentryof spentrocketstages,andthe

banningoffutureexplosionsinspace.

Asaresultofclassifyingeachorbiting

objectforthecomputermodel,it was

determinedthat the currentmajor

sourceofobjectsistheaccidental explosionof the secondstageof the

Deltarocket(tableI). Consequently,

new operationalrequirementshave

beenimplementedto preventfuture

explosionsof thisstage.

Figure1.---Orbital debrishazardandcontrol.

POSSIBLE MEASURES TO REDUCE HAZARD:

[_AN EXPLOSIONS

CON|ROL REENTRY

INCREASE SPACECRAF] SHIELDIN(;

REMOVE DEAD PAYLOADS, ROCKE[S, EIC.

BAN UN_IECESSARY RE[ EASE OF S HROIJDS, F,CL i S, E [ {;

29
Solid Polymer Electrolyte Fuel

Cell

The average electrical power requirements of the Space Shuttle have continued to increase as the system

design matures. This growing need for

power has put stress on the fuel cell

life capabilities, greatly reducing the

amount of useful life available for

flight. This, together with increased

hardware costs due to inflation, has

caused serious concern regarding the

continued use of alkaline fuel cells to

support future spacecraft. In the past

decade, the individual fuel cell power

requirements have increased from a 3-

kilowatt average onorbit and a 4.5-

kilowatt peak during ascent to a 6.5-

kilowatt average onorbit and a 10-

kilowatt peak during ascent. This has

resulted in a reduction of fuel celt life

expectancy from 20 missions to as low

as 4 missions depending on power

levels and mission profile. Increased

spacecraft turnaround time is also required for additional fuel celt

changeouts, more frequent fuel cell

refurbishments, and additional

purchases of fuel cell components to

support increased activity. As a result

of the average mission energy growth,

the Space Shuttle Program cost to

support the power generation system

is expected to increase dramatically.

Solid Polymer Electrolyte (SPE) acid

fuel cell technology was studied to

provide a fuel cell system that would

improve cost, weight, performance,

and efficiency while retaining the

desirable characteristic of operating

life. In addition, the SPE has the serendipitous characteristic of operating

propellant grade reactants. These

goals were met with a 1.1-square-foot

cell that was representative of a Shuttle-designed component (fig. 1). The

cell accumulated over 3200 hours of

invariant performance at a current

density range between 100 and 500

AtftL A tear down analysis of this cell

revealed no evidence of material

degradation.

An 18-cell stack of 1.1-square-foot

SPE cells (fig. 2) that represents onehalf of a Shuttle-configured fuel cell

has been assembled and a 2000-hour

demonstration test has been initiated.

After initial calibration, this hardware

will be tested specifically to the Shuttle qualification toad profile operating

at Shuttle conditions of onboard gasreactant pressures, temperatures, and

heat-rejection capabilities.

The goal of the program is to develop a

Space Shuttle fuel cell engineering

model of the Solid Polymer Electrolyte

type that is interchangeable with the

Shuttle alkaline type now being used.

This change would result in a weight

savings to the Orbiter of approximately

171 pounds and also would reduce the

average vehicle turnaround time significantly. Because the SPE fuel cell is

compatible with propulsion grade

reactants, a related weight reduction

option is also available. Recovery of

main propulsion system residual liquid

oxygen for use with the Solid Polymer

Electrolyte (only) fuel cells could provide an additional 1500-pound weight

savings on missions of 4 days or

longer. This option requires minor

plumbing changes to the Shuttle vehicle; however, these are considered to

be low-risk changes.

Figure 1.---Solid polymer electrolyte fuel cell components.

II

Figure 2.--A 7-kilowatt reactor stack with 18 cells.

3O
Space Construction Experiment

Concepts

Future space program plans include

spacecraft with a size and/or weight

that exceeds the volume limits or

boosts the capabilities of the Space

Transportation System (STS). Implementation of any of these programs

will require the capability to construct

large systems in space. These

systems will initially be constructed

from the Orbiter. Because the ability to

construct and operate large space

systems has not been demonstrated,

users may be reluctant to employ large

space structures concepts with the accompanying implications of high costs

and high risks. Several complex ambitious demonstration projects have

• been studied; however, none has

been of a practical size and cost that

could be implemented in a simple

Orbiter-based flight experiment.

The approach used was to evaluate

the construction requirements of the

several large systems that were being

examined in the Space Construction

System Analysis study. From this list,

concepts for flight experiments to

evaluate specific issues were generated. Three principal areas of technical concern are the actual construction

operations, the characteristics of the

dynamics of low-frequency structure,

and the ability to control the system

during and after construction.

Four flight experiment concepts

(fig. 1) were produced that, in conjunction with a ground test program,

could generate the technology base

needed to support construction of

future large space systems. An early

experiment concept was the use of the

Remote Manipulator System (RMS) to

deploy a structural subassembly, to

effect multipoint attachment of the

structure, and to install a simulated

equipment module. A subsequent experiment would exercise extravehicular activity (EVA) and support equipment to access a structure for the installation of lines and systems.

Another variation in the experiment

concept would evaluate the joining of

beam segments that might have been

fabricated in space by a beam

machine.

The interaction of a low-frequency

structure with the Orbiter might be

studied by the deployment of a long

boom that could replicate the dynamic

performance of a large structure element such as an antenna feed mast.

From the experiment concepts

developed, a concept may be

selected for a relatively simple early

flight experiment that will be valuable

in reducing the risk and uncertainty in

planning large systems later.

Figure 1.Gour flight experiment concepts.

31
Space Construction System

Analysis

Studies of large orbiting systems concepts have projected a need for assembly or construction in space to

achieve operational configurations.

Space construction methods and techniques need to be identified and

evaluated for various sizes and shapes

of structures. Although past studies

have evaluated various construction

methods, no detailed end-to-end

analysis has been performed of a

specific large space project system to

understand and evaluate the construction techniques, the construction support equipment required, the time

lines, the system installation/location,

and the extravehicular activity (EVA)

assisted subsystem installation and

checkout.

Part 2 of the study was initiated in

June 1979 to establish mission requirements and concepts for an

Engineering and Technology Verification Platform (ETVP). This platform

was selected to represent a future

system that would eliminate most of

the construction requirements envisioned through the decade of the

1990's. A detailed construction

analysis was performed of time lines,

Space Shuttle crew duty cycles, integrated lighting and power requirements, payload manifests, payload

bay packaging, Shuttle launch requirements, and overall analysis of

construction drivers. Determination of

requirements for early Shuttle flight

construction experiments was also

identified and evaluated. The use of

the ETVP as an advanced communications platform is shown in figure 1. A

multiple fabrication and assembly

concept used for construction of the

platform is shown in figure 2,

The study was concluded in June

1980. Study conclusions indicate the

following. Large space systems should

be designed for space construction

and constructed primarily by automated systems augmented by astronaut EVA. Uncertainties in space construction analysis must be resolved by

early ground and flight tests. Linear

structural configurations are preferred

over the other configurations studied

for Earth-oriented missions. Systems

installation design is determined by

construction and servicing requirements. Construction requirements

should be incorporated into ongoing

developments such as the open cherrypicker and the EVA mobility aids.

The results indicate that the Orbiter

can potentially be used as the construction facility; however, limitations

on Orbiter power/energy may constrain this type of activity.

Figure 1.--The Engineering Technology

Verification Platform in an advanced communicationsplatform configuration.

TRI-BEAM

7

 °°ULE7 Y ZOROITTOANS R

-_ _PAYLOAD X "_ '

-[ t ENGTH lOB METERS

-REACTION CONTROL HEIGHT 6.5 METERS

SYSTEM MODULE CROSSBEAM 17.4 METERS.

(4 PLACES! WEIGHT 30 4]5 KILOGRAMS

rh70SO POUNDS,

8 P L INTERFACE LOCATIONS

• TYPICAL PAYLOAD

(ANTENNA) INSTALLATION

60 KILOW,_¢ATT FDUAL POWER

EXTENSION PACKAGES ARRAy

Figure 2.--The multiple fabrication and assembly station concept for use in platform

construction.

STATION l

• FAB LONGITUDINAL BEAMS

• ASSEMBLY ANDINSTALLATION

• CHECK-OUT

G_AND SERVICE PORTS

32
Loads and Dynamics of VariableGeometry Structures

Nearly all methods for dynamic structural analysis are applicable only to

structures with fixed geometry.

However, for new concepts in large

space structures that require space

construction or deployment, the

capability is needed to predict

dynamic responses and loads

although the structural geometry is

varying. The most direct approach to

this problem -- obtaining solutions

using physical degrees of freedom --

requires too much computing time for

routine application on even moderatesize finite-element models. Therefore,

a more economical dynamic-analysis

method based on a reduced number of

coordinates is needed. In addition, it

would be desirable to develop innovative approaches by which the range of

applicability of standard fixedgeometry structural-analysis programs

such as NASTRAN could be extended

to solve at least some of the variablegeometry problems.

Several variable-geometry spacestructure concepts were reviewed in

order to select a configuration for exploring new analytical techniques. The

selected configuration is illustrated in

figure 1. Two separate construction

problems were studied. In the first

task, beam fabrication, a beam is constructed by an Automated Beam

Builder mounted in the Orbiter.

Because of the inclusion of a power

module with very flexible solar panels,

problem 1 forms the basis for investigating beam fabrication from a

flexible base. In the second task,

beam relocation, the completed beam

is grasped by the Remote Manipulator

System (RMS) and moved through a

large angle by rotating the manipulator

about its shoulder joint.

Simple mathematical models of

these structures were developed and

computer programs were written to

generate solutions by numerically integrating the equations of motion in

physical coordinates. The models included a simplified closed-loop

idealization of the Orbiter vernier

attitude-control system. A new

reduced-coordinate variable-geometry

method and an approximate technique

based on fixed-geometry methods

were then developed. Finally, physical

coordinate solutions were used

as a standard of comparison to evaluate the accuracy of the approximate

techniques.

Figure 1.---Study configuration of construction problems.

The modal-analysis approach conventionally used for reducing the size of

complex fixed-geometry problems

was extended to variable-geometry

problems. This new approach reduced

the computer time by 85 percent with

no appreciable loss in accuracy for the

problems that were investigated. A

sample time history generated with

the new modal method is shown in

figure 2. In this problem, a 100-meter

beam is being fabricated from the Orbiter while the control system is correcting a 1° initial attitude error about

each axis. The illustration shows the

Orbiter pitch angle, the beam fabrication rate, and the elastic deformation

of the beam relative to the Orbiter in

the fore-and-aft direction.

It was also demonstrated that the

dynamic response of the structure to

excitation resulting from variablegeometry motion could be accurately

determined by employing a standard

fixed-geometry program, such as

NASTRAN, in an innovative way. This

technique is useful for studying

responses during time intervals when

problems are expected; e.g., when a

sudden geometry change occurs,

although it is limited to time spans for

which the variation in geometry is

small.

1-METER

BEAM

RADIATOR

_'-- SOLAR

i_('_ _;,>_f_/_,,_ MANIPUL'ATOR

MODULE--J

ORBITER

AUTOMATIC

BEAM FABRICATION BEAM

BEAM RELOCATION BUILDER

PROBLEM 1:

PROBLEM 2."

Figure 2._ample time histories for beam

fabrication for the variable modal method,

.O200

- o_oo

ORBITER pITCH ANGLE

0-q fq j

i

VELOCiTy OF gElM OROWTH

a

_7 e

.8

AFT DISPLAC[M_NT of B[AM [pP

33
Manned Geosynchronous

Mission Requirements and

System Analysis

The NASA is presently developing a

manned Space Transportation System

(STS) to low Earth orbit (LEO).

However, advanced space mission

planning includes both manned lowEarth-orbit and manned geosynchronous-Earth-orbit (GEO) missions.

The activities potentially requiring

manned participation in both LEO and

GEO consist of construction, inspection, servicing, repairing, and operation of large space systems such as

communications, solar power, and

Earth observation satellite& To exploit

the capabilities of the Space Transportation System and to develop the full

potential of space operations, it is essential that developmental planning of

Orbital Transfer Vehicles (Ol-V's) be

expanded to include manned

capability.

The main objective of this effort is

to establish mission and systems opportunities and capability options for

various levels of manned activity requirements, and to synthesize crew

module and/or other manned system

support necessary for extension of

manned mission capability to geosynchronous orbit. This study emphasizes manned geosynchronous-orbit

sortie missions and associated crewsystem concepts.

accomplish all missions except a 30-

man crew rotation and supply mission.

All remaining missions can be accomplished with one MOTV flight to

orbit except the solar power satellite

demonstration mission that requires

four such flights because of the large

amount of mission hardware needed

to be transported to the construction

site.

In phase 2 of the study, a communications satellite servicing mission

was selected as the design reference

mission. In this mission, four communications satellites, all using the

standard Multimission Modular

Spacecraft (MMS) for subsystem support functions and all identical to each

other, are routinely serviced by the

MOTV. The satellites are all located

90 ° apart in geosynchronous Earth orbit. Periodically, the MOTV visits each

of these satellites and services the

MMS subsystems.

Some of the significant results of the

phase 1 and phase 2 portions of the

study are as follows,

1. Two- or three-man crews and a

mission of up to 30 days duration will

accomplish 85 percent of the proposed Orbital Transfer Vehicle missions.

2, A 1-1/2-stage propulsion system

concept (fig. 1) shows better performance and cost than a single- or twostage vehicle.

3. Proposed MOTV missions can

be accomplished with two to five STS

launches.

4. One Space Shuttle performs all

launches and loiter-mode recovery, A

typical four-launch mission engages

the Space Shuttle for 71 days.

5. The ground turnaround is

baselined but low-Earth-orbit platform

turnaround may be cost effective,

6. A capsule diameter of 3 meters

allows mission equipment to be

mounted externally,

7. Radiation protection requirements dictate that the capsule wall be

of 1.1-centimeter aluminum equivalent thickness.

8, Protection against solar proton

storms requires forecasting the size of

solar events.

9, A single-deck crew module is

preferred over a two-deck crew

module.

In phase 1 of the study, a broad range

of generic missions was selected from

which Manned Orbital Transfer Vehicle (MOTV) requirements were

derived. These generic missions were

divided into five categories as follows:

inspection, service, and repair; operation of a large space system; debris

removal; construction; and unmanned

cargo transport. The missions range

from short duration, two-man crews,

and low mission-hardware weight to

orbit to long duration, three-man

crews, and heavy mission-hardware

weight to orbit. The main objective

was to develop a versatile MOTV concept that would encompass most of

these generic missions with a

minimum of modifications. The concept that was selected was an all-propulsive MOTV using a 1-1/2-stage propulsion system and a 25.0-cubic

meter crew capsule. This concept can

Figure 1 .--A Manned Orbital Transfer Vehicle accomplishing transfer to geosynchronous

Earth orbit.

34
Fiber Optics Multiplexing

The monolithic integrated fiber optic

terminal is being developed to use

guided-wave optical technology to

produce a passive optical wavelength

multiplexing/demultiplexing system

with a single-mode optical fiber serving as the transmission medium. The

use of fiber optics for data handling

and transmission is expanding rapidly

in military and aerospace systems and

in commercial applications. Significant advantages of using fiber optics

for aerospace vehicle design are complete channel isolation, wide bandwidth, reduced electromagnetic interference susceptibility, small terminal

size, low weight, reliability, and an

ultimately lower cost.

The optical multiplexer/demultiplexer

is an advanced technological instrument that provides for simultaneous

transmission of multiple channels over

a single fiber. The approach is

wavelength multiplexing using "n" injection laser diodes biased to the lasing threshold and modulated by the input data. The lasers, each of which

differ in output wavelength by an

amount _X. = 17 nanometers, are

coupled into the integrated optical

transmitter/multiplexer chip that uses

a chirped waveguide diffraction grating to combine the spatially separate

laser beams to produce a singlewavelength multiplexed beam. The

multiplexed beam is coupled to a

single-mode fiber for transmission.

The output of the fiber is coupled to

the integrated optical demultiplexer

that separates the input beam into "n"

separate beams that are absorbed by

"n" P-I-N detectors. The detector output is an electrical signal representing

the original input signal to the

transmitter.

The primary emphasis has been on

the demultiplexer development and

demonstration. Currently, the demultiplexer (fig. 1) has been

developed and is undergoing refinement. Emphasis is also shifting to the

optical multiplexer. This activity has

required significant technology

developments in manufacturing processes and techniques for integrated

optics construction. This includes ionbeam milling of diffraction gratings,

optical lenses, and fiber-to-waveguide

coupling.

Figure 1 .fiber optics multiwavelength demultiplexer.

TEST JIG

/

DIFFRACTION GRATING

/

//

\

\.

LUNEBERG LENS

FIBER COUPLING

35
High-Power Traveling-WaveTube Amplifier

To increase the capability and range

of spacecraft communications operation, higher power levels are needed.

For manned spacecraft that require a

cold plate interface with the environmental control system, the radiofrequency power output has been limited

to approximately 120 watts. This

limitation is due to inefficient methods

of dissipating heat produced by the

tube at higher power levels. Attempts

to overcome this problem have

generally led to decreased reliability

and excessively heavy packages. The

purpose of this project was to design a

highly efficient high-power S-band

traveling-wave tube that is both lightweight and highly reliable and that

also demonstrates a "state-of-the-art"

approach to cooling design.

A program was initiated to build a

high-power high-efficiency travelingwave tube using heat pipes in the

base of the tube for cooling. Velocitytapering and multistage collectors

were used to provide a high overall

efficiency. Integral heat pipes with

stainless steel wicks were chosen

using ammonia as the working fluid.

Ten heat pipes were used in the

baseplate, six transverse and four

longitudinal. The majority of these

heat pipes were placed near the hot

spot of the tube, the collector, which is

located at the output end of the tube.

The result of this project is a 300-watt

traveling-wave tube (fig. 1) that is both

electrically and thermally efficient.

Testing at the Johnson Space Center

indicates that this efficiency is accomplished without sacrificing other

performance criteria such as low noise

power density, low AM/PM conversion,

low voltage standing-wave ratio, and a

low level of harmonic and spurious

signals. The traveling-wave tube is

capable of producing more than 321

watts output at more than 54 percent

efficiency. This efficiency is accomplished with a maximum baseplate temperature of 121 ° F by using a

small blower on the cold plate. Heat

pipes will be used extensively in tube

design in the future not only for increased power capability but also for

improved reliability.

Figure 1.--Traveling-wave tube.

36
Office of

Aeronautics

and Space

Technology

Significant Tasks

41 Shuttle-Launched Research Vehicle

Funded by: Aeronautics Research and Technology Base (UPN-505)

(Subauthorization from Langley Research Center)

Aeronautics System Studies (UPN-791)

Technical Monitor: J. T. Visentine/ED4

Task Performed by: General Electric Company

Reentry Systems Division

Contract NAS 9-15977

42 Orbiter Experiments Project Support and Integration

Funded by: Space Technology Shuttle Payloads (UPN-543)

Technical Monitor: J. M. Sanders/ED4

Task Performed by: Rockwell international

Contract NAS 9-14000

Lockheed Engineering and Management

Services Company, Inc.

Contract NAS 9-15800

Bendix Communications Division

(Aerodynamic Coefficient identification Package)

Contract NAS 9-15588

44 Solar Power Satellite System Definition and Critical Supporting Investigations

Funded by: Energy Systems Development (UPN-775)

(Reimbursable funds provided by the Department of

Energy)

Technical Monitor: T. E. Redding/EB

Task Performed by: Boeing Aerospace Company

Contract NAS 9-15636

University of Texas

(SPS Microwave/Ionosphere

Interaction Experiment)

Contract NAS 9-16086

46 Electrochemical Orbital Energy Storage Program

Funded by: Space Research and Technology Base (UPN-506)

Technical Monitor: Hoyt McBryar/EP5

Task Performed by: General Electric Company

Contract NAS 9-15831

47 Space Constructable Heat Pipe Radiators

Funded by: Supporting Development (UPN-906)

Space Research and Technology Base (UPN-506)

Technical Monitor: W. E. Ellis/EC2

Task Performed by: Grumman Aerospace Corporation

Contract NAS 9-15965

37
48

5O

51

Space Plasma Interaction Experiments for Large Power

Systems

Funded by: Space Research and Technology Base (UPN-506)

Technical Monitor: J. E. McCoy/SN3

Task Performed by: Northrop Services, Inc.

Contract NAS 9-15425

Lockheed Engineering and

Management Services Company, Inc.

Contract NAS 9-15800

Houston Baptist University

Contract NSG-9076

Rice University

Contract NAS 9-15796

Contract NAS 9-16206

Lee Parker, Inc.

Contract NAS 9-15934

Advanced Manned Vehicle Onboard Propulsion Technology

Funded by: Space Research and Technology Base (UPN-506)

Technical Monitor: M. F. Lausten/EP2

Task Performed by: Aerojet Liquid Rocket Company

Contract NAS 9-15724

Contract NAS 9-15958

Advanced Synthetic Aperture Radar Technology

Funded by: Space Research and Technology Base (UPN-506)

Technical Monitor: K. Krishen/ED6

Task Performed by: Jet Propulsion Laboratory

Contract NAS 7-100

Texas A&M University

Contract NAS 9-16102

Environmental Research Institute

of Michigan

Contract NAS 9-16135

New Mexico State University

Contract NAS 9-16092

University of Texas

Contract NAS 9-16171

Lockheed Engineering and

Management Services Company, Inc.

Contract NAS 9-15800

38
52 Large Space Systems Technology

Funded by: Space Systems Technology Program (UPN-542)

(Subauthorization from Langley Research Center)

Technical Monitor: L. M. Jenkins/EB

Task Performed by: McDonnell Douglas Corporation

(Advanced Space Platform Technology Study)

Contract NAS 9-16001

General Dynamics, Convair Division

(Forming and Welding of Graphite

Composite Materials)

Contract NAS 9-15532

Northrop Services, Inc.

Contract NAS 9-15425

53 Application of Advanced Electric/Electronic

Technology to Commercial Aircraft

Funded by: Aeronautics System Studies (UPN-791)

Technical Monitor: J. P. BighamlEH

Task Performed by: Lockheed California Company

Contract NAS 9-15863

54 Nonterrestrial Materials for Space Use

Funded by: Space Research and Technology Base (UPN-506)

Space Systems Studies (UPN-790)

Technical Monitor: R. J. Williams/SN7

Task Performed by: Lockheed Electronics Company, Inc.

(Handbook of Lunar Materials)

Contract NAS 9-15800

Lunar and Planetary Institute

Contract NSR 09-051-001

55 Fire-Resistant Low-Smoke-Generating Thermally Stable End

Items for Aircraft and Spacecraft

Funded by'. Aeronautics Research and Technology Base (UPN-505)

Systems Technology Programs (UPN-534)

Technical Monitor: E. E. Supkis/ES5

Task Performed by: General Electric Company

Contract NAS 9-15763

Contract NAS 9-15533

McDonnell Douglas Corporation

Contract NAS 9-15591

Northrop Services, Inc.

Contract NAS 9-15425

39
56

57

Toxicity Testing and Evaluation of Candidate Aircraft

Materials

Funded by: Materials and Structures Systems Technology (UPN-543)

Technical Monitor: Carolyn Leach Huntoon/SD4

Task Performed by: Northrop Services, Inc.

Contract NAS 9-15425

Southwest Foundation for Research and Education

Contract NAS 9-15690

Adsorption Pumping Cryogenic Refrigeration

Funded by: Space Researchand Technology Base (UPN-506)

Technical Monitor: R. R RichardtED6

Task Performed by: University of Texas

Contract NAS 9-14491

40
Shuttle-Launched Research

Vehicle

The initiation of operational Space

Shuttle Orbiter flights in the 1980's

will provide the aerospace community

with many unique opportunities to

demonstrate and evaluate advanced

space vehicle design concepts. The

narrow entry corridor of the Orbiter and

the inherent limitations of groundbased laboratories to simulate entry

and aerothermal flight environments

dictate a need for a separate category

of entry research vehicles. The frequency of flights into space by the

Orbiter will provide a recurring

capability to carry advanced unmanned aerospace vehicles into Earth

orbit and perform research and technology demonstrations in many related disciplines while these vehicles

maneuver, enter, and fly in the upper

atmosphere before initiating a landbased recovery.

The Shuttle-Launched Research

Vehicle (SLRV) program will enable

the NASA flight research centers to expand their knowledge in entry and hypersonic technologies for future

developments in the Earth and planetary space programs, and will provide

principal investigators with a dynamic

flight research facility that will lead to

new generations of operational space

flight vehicles.

The SLRV would be used to demonstrate new technology concepts in hypersonic flight environments that lie

outside the operational envelope of

the Shuttle Orbiter. These concepts

include aeromaneuvering systems for

reusable orbital transfer vehicles, advanced thermal protection system

materials for planetary entry probes

and Earth-to-orbit vehicles, and

control-configured designs for heavylift launch vehicles.

The SLRV program uses the Orbiter's payload capability for advanced

technology research and development

and extends the aerodynamic and

aerothermodynamic research that will

be conducted from the Space Shuttle

during the Orbiter Experiments Program.

The SLRV concept provides a common

electronics "core" system to which

various aeroshell or fuselage configurations can be attached. This

"core" will provide all normal avionics,

control, data, communications, power,

and maneuvering capability for unmanned subscale reentry vehicles. Experiments selected for these vehicles

would be designed to provide

research data to support the Office of

Aeronautics and Space Technology

research programs in advanced space

transportation systems and planetary

entry technology. Aeroshell and

fuselage configurations would satisfy

specific experimental objectives and

would fall into three categories:

ballistic, medium lift-to-drag (L/D)

ratio lifting bodies, and high LID ratio

lifting bodies.

The SLRV development program is

designed with primary emphasis

directed toward cost-effectiveness.

This program employs a phased programmatic approach whereby

development of the flight vehicles will

be initiated on a modest scale. Major

decisions for subsequent growth will

follow technical advancements made

during earlier phases of the flight

research program and will include the

research data obtained from the Orbiter Experiments Program.

Significant program activities accomplished this year at JSC include

initiation of an SLRV applications and

cost-benefits study and completion of

two interagency reviews of the

preliminary study conclusions, candidate applications, and proposed vehicle configurations.

The purpose of the study is to conduct a cost-benefits analysis of various

combinations of SLRV's and research

and technology experiments. The

results of the analysis wilt be used to

define a flight test program to advance

hypersonic reentry and cruise-flight

technology required for the development of advanced space transportation systems.

This study has resulted in the identification of 28 research and technology experiments and 3 candidate

vehicle configurations for the SLRV.

These vehicle configurations include

ballistic, fixed-trim, and variable-trim.

The variable-trim vehicle (fig. 1) provides the greatest versatility. This

vehicle will use split windward flaps to

fly at various angles of attack during

entry. It will flight test both windward

and leeward advanced thermal protection system design concepts and

advanced flight control systems in

severe reentry environments within

reentry corridors that are unattainable

using the Shuttle Orbiter.

Figure 1.----Maneuverable Shuttle-launched research vehicle (split windward flap configuration).

TRANSMITTER AND I PARACHUTE PACKAGE

SIGNAL CONDITIONER • DROGUE CHUTE AND MORTAR

• DECELERATION CHUTE

POWER N TANK • MAIN CHUTE

CONDITIONER 2

DROGUE CHUTE AND MORTAR

BATTERY ROCKET • DECEL CHUTE

IMU HELIUM TANK MOTOR • MAIN CHUTE

IN-FLIGHT

BALLAST 7 + __ _ DISCONNECT

1:)+

15 = ROCKET

MOTOR

FLAPS IN NOMINAL

FLAPS IN MAX POSITION

RETRACTED r

, p LAPS IN 25 ° , MAX

AUTOPrLOT OSITION EXTENDED POSITION

MULTICODER ZLES

-YAW, 2 PLACES- -PITCH AND ROLL, 4 PLACESDAT_ _I_(_'E S-- VEHICLE PROPERTIES

SYSTEM _ WEIGHT: 2298 LBS

r --..._2_o W _CLA; 138 AT'" _ 20 +

LENGTH" 180 IN

FLAPS SHOWN AT MAX BASE DIA" 75 IN.

EXTENDED POSITION RN: 5.6 IN

41
Orbiter Experiments Project

Support and Integration

As a pioneer (launch to landing) space

vehicle, the Space Shuttle Orbiter

has the potential of providing costeffective research and technology

data needed for the development of a

broad spectrum of future aerospace

vehicle designs or enhancements.

Although the Orbiter includes instrumentation necessary to perform

design verification and to monitor

select operations functions, the

baseline Orbiter flight test and operations program does not include plans

to collect specific research and technology data relevant to the design of

future vehicles.

To capitalize on the opportunity to use

the Space Shuttle as a means of acquiring flight data for a wide variety of

technology disciplines related to vehicle design, the Office of Aeronautics

and Space Technology has established the Orbiter Experiments Program, which uses the Orbiter as a

flight research vehicle (fig. 1). JSC

continues to support the Orbiter Experiments Program by providing (1)

overall integration management and

program planning, (2) technical

development for specific experiments,

and (3) integration of experiments into

the Orbiter. The Orbiter experiments

are designed (1) to augment the

research and technology base for

verification or enhancement of the

operational efficiency of current and

future aerospace vehicle design by

collecting Orbiter flight data in all related technology disciplines, and (2)

to correlate ground-based data with

flight data by developing procedures

to accurately extrapolate groundbased facility results to flight conditions.

All experiments in phase I have

been "prioritized" from a flight

spectrum that includes launch, orbit,

and entry maneuvers. The experiments are selected by using the principles of development and succession. This unique approach has been

cost-effective because of the maximum use of in-place hardware.

To obtain aerodynamic data during

launch, orbit, and entry, the Aerodynamic Coefficient Identification

Package (ACIP) has been installed on

the Orbiter at Kennedy Space Center.

It is expected to fly on all Orbiter

flights through 1983. The ACIP hardware has undergone post-installation

functional tests that included elevon

calibration and dynamic stability tests.

An underflight of the Shuttle Orbiter

is planned during entry of the first Orbiter flight to obtain an infrared image

of the thermal protection system of the

Orbiter. This project is known as the

Infrared Imagery of Shuttle (IRIS) experiment. Flight experiment testing of

the hardware mounted in an aircraft

continues.

Figure 1..--Orbiter ExperimentsProgram.

SHUTTLE INFRARED LEESIDE

TEMPERATURE SENSING

(SILTS)

IR SCANNER

IN DEVELOPMENT CYCLE

AERODYNAMIC COEFFICIENT

IDENTIFICATION PACKAGE

(ACIP)

PITCH CG AXIS

LOCATION

INSTALLATION COMPLETE

SHUTTLE ENTRY AIR DATA

SYSTEM (SEADS)

STAGNATION

PRESSURE

IN DEVELOPMENT CYCLE

DYNAMIC, ACOUSTIC AND

THERMAL ENVIRONMENT

)DATE)

PAYLOAD WITH

ENVIRONMENTAL

SENSORS

ADDED TO DEVELOPMENT CYCLE

THERMAL PROTECTION SYSTEM

)TILE GAP HEATING)

CONTROL L E D GAP

TOL E R &NCE

APPROVED FOR FLIGHT

THERMAL PROTECTION SYSTEM

)CATALYTIC SURFACE EFFECTS)

THERMOCOUPLES

APPROVED FOR FLIGHT

SHUTTLE UPPER ATMOSPHERE

MASS SPECTROMETER (SUMS)

NOS_-

CA._

_JAS S!f_E AM

IN DEVELOPMENT CYCLE

INFRARED IMAGERY OF

SHUTTLE )IRIS)

iR

TELESCOPE #*

INSTALLATION COMPLETE .=

42
The thermal protection system experiments (Catalytic Surface Effects

and Tile Gap Heating) have been

assembled in kit form and are ready to

ship to the Kennedy Space Center for

installation. Hardware for both experiments is scheduled to be flown on six

flights starting with the second Orbiter

flight.

Three experiments in the development and checkout cycle include the

Shuttle Infrared Leeside Temperature

Sensing (SILTS), the Shuttle Upper

Atmosphere Mass Spectrometer

(SUMS), and the Shuttle Entry Air Data

System (SEADS). A volume fit check

of the SUMS hardware in the Orbiter

vehicle and the SILTS hardware in the

pod, which will be mounted on top of

the Orbiter vertical stabilizer, has been

accomplished. Electrical checkout of

the SILTS hardware is continuing.

The Dynamic, Acoustic, and Thermal Environment (DATE) experiment

has been added to the development

cycle. The DATE experiment for STS-1

will use data from the existing

Development Flight Instrumentation

(DFI) system. Development of DATE

hardware for Orbiter flights 2 through 4

includes a composite of Air Force and

sponsoring NASA center requirements.

For the experiments in phase I, a

transportable Orbiter experiments

ground data processing station for use

at the Kennedy Space Center is being

validated (fig. 2). Data processing requirements for all hardware and

analytical experiments for the first Orbiter flight have been published. In

addition, 1 7 new phase tl experiments

in four technology disciplines have

been approved for definition and are

listed below.

Aerodynamics/aerothermodynamics

1. Shuttle Windward Entry Aerothermodynamic Experiment

2. Data Quality Enhancement for

Stability and Control Technology

Research

3. ACIP/Pulse Code Modulator II

4. Programed Test Input Software

for Stability and Control Technology

Research

Materials and structures

5. Structural Temperature Experiment

6. Photogrammetric Structural

Monitoring Experiment

7. Advanced Nonmetallic Thermal

Protection System Materials

8. Effect of Orbiter Flight Environment on Bearing/Lubricant System

9. Metallic Thermal Protection

System Experiment

10. DATE II

11. Space Applied Thermal Protection System Materials Experiment

12. Catalytic Effects in Stagnation

Regions

Electronics and human factors

13. Advanced Autopilot Experiment

14. Shuttle Altitude Measurement

System

15. Free Drift Attitude Modes Experiment

16 Orbiter Flying Qualities

Propulsion and power

17. Particle Energy Detection Experiment

Figure 2.--Transportable Orbiter Experiments ground data processing station.

• i]]_ _qq

:i 1

J

43
Solar Power Satellite System

Definition and Critical

Supporting Investigations

The possibility of generating large

quantities of electrical power in space

and transmitting it to Earth by

satelhtes was first suggested in 1968.

The solar power satellite (SPS) concept would provide an almost continuous supply of power to utility

systems without consuming nonrenewable fuels. During the years

following 1968, several studies of the

SPS concept were conducted by

NASA and industry. The energy shortage of 1973 spurred interest in the

concept and in early 1976 the Department of Energy (DOE) (then the

Energy Research and Development

Administration) and NASA initiated

the Solar Power Satellite Concept

Development and Evaluation Program.

This evaluation program is guided by a

joint DOE/NASA plan that covers the

period from mid-1977 to mid-1980.

The basic objective of the SPS system

definition studies is to define and

characterize environmentally acceptable and economically competitive SPS

systems.

The first milestone of the joint

DOE/NASA SPS evaluation and

development program was completed

with the delivery of the Reference

Concept Document in October 1978

Figure 1 shows the configuration of the

SPS Reference System that used optional silicon or gatlium-atuminumarsenide solar cells for energy conversion. The reference system document

was prepared by JSC and included

data developed by both Marshall

Space Flight Center and JSC. It has

been used as a reference point for the

DOE in conducting their studies within

the joint program. The DOE has made

extensive use of this document in performing environmental, comparative,

and socioeconomic assessments.

Beginning in fiscal year 1979, the

funds for this program have been provided by the DOE. The funds at JSC

were used for continued system

definition studies and critical supporting investigations.

The DOE/NASA SPS Concept

Development and Evaluation Program

will be concluded in 1980 with the issuance by DOE of the Program

Assessment Report. Continued efforts

will depend on program recommendations following the completion of this

report.

Figure 1.---Solar Power Satellite Reference System.

SILICON

j_. :'_52 O0 m

J _. _f'::'_i)!'':_ ._"_470 ,,,

1°s°2 2 som

ALUMINUM 5 m

ARSENIDE .

I0 ,500 rn

SOLAR BLANKET AREA

TOTAL AREA

SOLAR CONCENTRATION RATIO

SILICON

52 km 2

54 km 2

GALLIUM

ALUMINUM

ARSENIDE

26 km 2

55 km 2

1 2

During fiscal year 1980, system definition studies were continued with

emphasis on determining reference

system costs; defining alternative concepts; and conducting workshops in

the technical areas of microwave

power transmission, space structures

and construction, energy conversion

and power management, and space

transportation. Summary reports were

also submitted in support of the Program Assessment Report prepared by

the DOE.

The alternative systems investigated included laser power transmission, reduced-size payload launch

vehicles, and solid-state microwave

systems. Studies of laser power

transmission showed high satellite

mass (more than twice that of the

reference system) and atmospheric

absorption of the laser energy as major

concerns relative to microwave

systems. A breakthrough in laser technology, however, could change this

conclusion. The reduced-size payload

launch vehicle study indicated that a

120-metric-ton payload vehicle would

be more cost-effective and would

have less environmental impact than

the reference system 420-metric-ton

vehicle.

The solid-state microwave system

satellite concept using antennamounted converter devices optimizes

at a lower power than the klystron tube

systems and should have a higher

reliability; however, the cost per

kilowatt would be about 25 percent

greater than for the reference system.

Critical supporting investigations

were completed in the areas of solidstate combining device assessment,

fiber optics investigations (for phase

control system circuits), and

retrodirective phase control breadboard system evaluations. A space

structures control analysis effort conducted by the Jet Propulsion Laboratory for JSC was continued with completion scheduled for early 1981.

Investigations were also continued

in the area of ionospheric testing. The

microwave beam transmitting energy

from a proposed solar power satellite

in geosynchronous orbit to a ground

receiving antenna (rectenna) will interact with the ionosphere by heating

the free electrons in the ionosphere. A

beam power density of 23 mW/cm 2

was originally proposed as a threshold

for nonlinear interactions with the

44
ionosphere. A numberof theoretical

andexperimental studies,sponsored

by the Department of Energy,using

the 1000-footantenna(fig. 2) at

Arecibo, Puerto Rico, and the

ionosphericheatingfacility(fig.3) at

Plattville,Colorado,havebeencompleted.Thepurposeof thesestudies

wastoascertainionosphericthreshold

levelsandtodeterminetheassociated

impacts on communicationand

navigationsystems.Theresultsindicatethattheoriginal23-mWlcm2 limit

was conservative and can possibly be

raised. Effects produced by simulated

SPS heating are many times less than

those from natural ionospheric disturbances as introduced by solar flares.

The ionospheric power density limit is

a critical SPS system sizing parameter

and has a significant impact upon the

cost of electricity. A higher limit allows

more power to be delivered to a

smaller rectenna.

In addition to the DOE studies on SPS

impacts to communication and

navigation systems, NASA conducted

tests to determine the effects of errors

introduced into the SPS phase control

system by a heated ionosphere. The

uplink phasing signal is transmitted

directly through the center of the

heated ionospheric region. The NASA

tests used polar-orbiting NAVSAT

satellites transmitting two coherent

signals in the 150- to 450-megahertz

frequency band through an ionosphere

heated by the Plattville, Colorado,

facility. Differential Doppler measurements were made to map electron

density profiles. A phase perturbation

model will use these profiles to predict

phase perturbations on a 2.45-

gigahertz uplink signal.

An analysis of phase fluctuations on

a radio star signal through an unheated

ionosphere has been made using data

obtained from the National Radio

Astronomy Observatory in Socorro,

New Mexico. Thirteen sets of interferometers, each using two 25-meter

antennas, yielded data indicating the

phase fluctuations through an unheated ionosphere should be less than

1° during the 0.25-second period of

the uplink/downlink signals. The final

results of this analysis will serve as a

comparison with phase fluctuations induced by a heated ionosphere, as

measured in proposed 1981 tests

using the Arecibo, Puerto Rico, heating

facility.

Figure 2.--Arecibo, Puerto Rico, observatory ionospheric heating test.

DIAGNOSTIC RADAR

GUADALUPE ISLAND

Figure 3.-- Plattville, Colorado ionospheric heating test.

-R-EARTH-ORBITING

......... :" NAVSAT SATELLITE

MOraLE #-"fGROUND

RECEIVER

45
Electrochemical Orbital Energy

Storage Program

The separation of water into hydrogen

and oxygen by the passage of an

electric current through an aqueous

medium is essentially the reverse

reaction of a fuel cell. The fuel cell has

been the primary electrical power

source for all U.S. manned space programs (except Mercury) because of

superior flexibility, weight, and cost

factors and continues to be the most

viable candidate for 1 to 2 week missions to be conducted using the Shuttle. Since the Shuttle transportation

system will probably be the space

"workhorse" throughout the remainder

of the 20th century (perhaps beyond),

fuel cell electrochemical devices and

derivatives (electrolysis cells) will

have a major role in the conduct of the

missions assigned to NASA.

In a regenerative fuel cell configuration, the role of fuel cells -- in

addition to providing electrical power

to the vehicle and to the experiments

on the dark side of the orbit -- is to

provide potable water for the crew and

for certain thermal control requirements. The role of electrolysis cells is

to recycle fuel-celt-produced water

(and makeup water) using solar-arrayproduced power on the light side of

the orbit and thus provide power for

extending mission duration and/or

enhancing mission flexibility.

become a substantial portion of the lift

capability of launch vehicles. The

solar-powered space station definition

study of 1971 showed a weight and

cost advantage using a solar-powered

regenerative fuel cell system integrated with the life support system for

a six-man, 25-kilowatt space station.

Subsequent detailed design and

analysis studies expanded the results

and established definitive concepts.

More recent studies associated with

solar-powered space construction

facilities indicate the potential of integrating certain propulsion requirements into the system. Thus, the

regenerative fuel cell concept could

serve as an orbiting utility substation. It

is anticipated that this concept will be

proven with a field test of an engineering model in 1986 and that the technology will be available for orbital

emplacement by the late 1980's or

early 1990's. Figure 1 illustrates how

this system integrates electrical and

life support functions.

The responsibility for this technology development is shared by JSC

and the Lewis Research Center

(LeRC). JSC has the acidic technology

with the solid polymer electrolyte

membrane and LeRC has the alkaline

technology that is derived from the

Shuttle capillary matrix fuel cell. LeRC

is developing an alkaline "breadboard" article for testing at JSC.

The outstanding features of the

solid polymer electrolyte concept include the extremely long-life capability of the electrolytic membrane, the

superior efficiency of the electrolysis

cell, and the ability to operate at high

pressure. The alkaline capillary matrix

concept is presently superior in fuel

cell efficiency and shows promise of

improved efficiency in the electrolysis mode with recently developed

catalyst/electrode configurations.

A program was initiated in 1979 with

the objective of bringing the regenerative fuel cell energy storage concept

into technological readiness by 1986.

One task was to perform an in-depth

state-of-the-art study to define the

various elements of the system. That

task was completed with the publication of a state-of-the-art report in

November 1979.

Recycling of water in a regenerative

system is an increasingly important

consideration in space missions. In

addition to regenerating the hydrogen

and oxygen required for the fuel celt,

anticipated propulsion system propellants are almost exclusively hydrogen and oxygen, and space

manufacturing may use large quantities of hydrogen and oxygen for

various processes. Thus, metabolic

waste water that may be undesirable

for recycling for metabolic use may be

diverted to propulsion and/or to

manufacturing requirements yielding

multiple uses from a single commodity.

The expendables required for

electrical power and propulsion and

the life support systems required for

long-duration manned space missions, such as work crews for space

station or satellite construction, will

46

Figure 1.--Integrated regenerative energystorage,
SpaceConstructableHeatPipe

Radiators

The primary means for rejecting heat

from orbiting spacecraft is through a

space radiator system that rejects heat

from a fluid circulating through it by

radiation to the space environment.

Current systems use a mechanically

pumped coolant circuit to transfer heat

over the radiating surface. Because

system operation is vulnerable to complete failure from a single meteoroid

penetration, reliability over long mission durations is low. High reliability in

a pumped fluid system can be

achieved, but the system is generally

heavy because of the required redundant plumbing, pumping, and valving

hardware. Long-duration high-power

space missions wilt include excessively heavy heat-rejection subsystems unless significant technical

improvements can be made.

Therefore, a long-life heat-rejection

system that can be constructed and

deployed onorbit is required to support

future tong-term high-power missions

such as large space structures,

geostationary platforms, or spacehabitable modules.

The solution to this problem is to

develop a radiator system that can be

assembled from a small number of

relatively large elements (limited only

by the size of the Orbiter payload bay)

so that overall system complexity is

minimized. A space-constructable

radiator system, the keystone of which

is an innovative high-capacity heat

pipe design, will fulfill this requirement. This design, if successfully

developed, will allow future large

heat-rejection systems to be built up

to virtually any desired size (heat load

capability) using a relatively small

number of components. The large heat

pipes with radiator fins attached would

be "plugged in" to contact heat exchangers that provide heat from a

centralized heat-transport toop (fig.1).

Such systems would be relatively insensitive to the micrometeoroid environment of space as the puncture of

any module would cause only the loss

of that module's 2-kilowatt capability,

rather than the loss of all or a significant portion of the entire system. This

type of system would lend itself to

onorbit maintenance by simply

unplugging damaged heat pipes and

substituting new ones. The damaged

pipes could be returned by the Shuttle

for refurbishment and later reuse. The

relative simplicity of this design could

lead to the eventual manufacturing of

the heat pipes in space for use on very

large-scale structures.

The initial effort of this task has been

concentrated on a feasibility demonstration of the simple dual-passage

high-performance heat pipe design

that forms the basic component of the

system. This design permits high

heat-transport capability without impacting heat-transfer efficiency. It

combines the advantages of axial

grooves, such as simple construction

and large liquid and vapor areas, with

the high heat-transfer coefficients of

circumferential wall grooves.

The basic design of the improved

high-performance grooved heat pipe

contains two large axial channels, one

for vapor and one for liquid (inset, fig.

1), that permit the axial transport and

radial heat-transfer requirements to be

handled independently. The small slot

separating the channels creates a

high capillary pressure difference that,

coupled with the minimized flow resistance of the two separate channels,

results in the high axial heat-transport

capability. The high evaporation and

condensation film coefficients are provided separately by circumferential

grooves in the walls of the vapor channel without interfering with the overall

heat-transport capability of the axial

grooves.

Results of thermal bench tests of

small-scale (30-inch-long)laboratory

elements have confirmed the basic

operating characteristics of the dualpassage design and indicated its

feasibility for the desired application.

Current effort calls for the fabrication

and testing of a breadboard model

(approximately 20 feet long) of the

heat pipe to further demonstrate its

heat-transport capabilities, followed

by a demonstration of the manufacturability and performance capability

of a full-scale (approximately 60 feet

long) heat pipe. Development of the

heat pipe will be followed by a

preliminary design of a complete

radiator system flight prototype during

calendar year 1981. Design, fabrication, and checkout of a prototype test

article comprising a representative

portion of a complete system is

planned for calendar year 1982,

followed by thermal-vacuum testing in

January 1983.

Figure 1 .--Mockup of onorbit assembly of heat pipes with high-performance groove concept for

efficient large-scale heat rejection.

47
Space Plasma Interaction

Experiments for Large Power

Systems

The interactions between the space

plasma environment and surfaces elevated to high voltage (especially combinations of conducting and insulating

surfaces such as solar arrays) are complex. These interactions must be understood to develop the design criteria

necessary to build large high-voltage

power systems for space.

In determining design criteria for

space development testing, the large

vacuum chamber at JSC can provide a

vital intermediate "quasi-space" test

with scaling parameters intermediate

between the large ratio of object size

to sheath size for testing associated

with large space systems such as the

solar power satellite (SPS) system and

the small ratio testing in the small

chambers. The technology to be

developed is important to an increasing number of programs presently

being identified for Shuttle era operations. Large-scale high-voltage interactions with the space plasma environment are inherent in such diverse

systems as electric (ion thruster) propulsion, the various SPS subsystems

and large-scale space energy

systems, geomagnetic induction

power supply, and various high-energy

electron/proton beam experiments

proposed for magnetospheric and

space manufacturing studies. In addition to these intentionally exposed

high-voltage devices, it has been observed that many supposedly passive

surfaces acquire high-voltage potentials from time to time due to space

environmental interactions, particularly in geosynchronous orbit.

The program employs the unique 20-

meter-diameter Space Plasma

Laboratory facility at JSC to provide

simulated space plasma conditions for

testing large models. Adequate room

is available for free-space development of the high-voltage plasma

sheaths without the usual limitations

inherent to laboratory testing due to

wall effects and scaling errors. The

work is conducted in close coordination with existing laboratory and flight

projects at the Lewis Research Center

and is one part of the proposed joint

Air Force/NASA Environmental Interaction Technology Investigation.

Plasma may be generated either

stationary or with a flow velocity to

simulate the proper motion of a

satellite through the ionosphere with

the magnetic field variable from 0.1 to

3 gauss. The large sizes involved (both

the test object and the high-voltage

sheath) wilt allow direct measurement

of variations of plasma parameters

within the sheaths for detailed

verification of analytical model

behavior predictions. The Space

Plasma Laboratory experimental program is intended to provide a direct

link between smaller scale experimental data, analytical models, and

space-flight systems. The intermediate scale experimental capability is

important to avoid the large errors

often encountered when attempting to

scale hypothetical plasma behavior

beyond an existing smaller scale data

base.

From April to July 1980, the large

vacuum chamber at JSC was used to

perform several experiments in a

simulated low-Earth-orbit/ionospheric

space plasma environment. In addition to extending earlier studies (1977

and 1979) of large-scale plasma interactions with lO-square-meter highvoltage test panels, initial engineering

verification tests were performed

using a prototype Power Extension

Package (PEP) solar array module in

"flight" configuration. The 15- by 80-

inch array, consisting of 174 ultrathin

6- by 6-centimeter solar cells mounted

on a 2-mil Kapton substrate, is

designed to produce 75 watts from

each module. Each module weighs

less than 3 kilograms and is designed

for mechanical mounting by means of

40-mil hinge pins along each long

edge, allowing series or parallel connection of successive modules to obtain 10 to 25 kilowatts total power.

The prototype PEP array was performance tested under conditions of

solar thermal-vacuum and low-Earthorbit plasma, both separately and in

combination, to fully explore and verify

its response under actual space operational conditions (fig. 1). The results

verify satisfactory performance under

combined solar and plasma conditions

with plasma leakage current losses

less than 2 percent at array voltages

up to +280 volts (+80-volt solar array

output plus 200-volt bias). Arcing to

the plasma was observed at voltages

over 500 but was shown to cause no

Figure 1.---Power Extension Package solar

array under combined solar, thermalvacuum, and simulated low-orbit plasma

test exposure in chamber A.

48
damagetothearray(fig.2).Insulation

of the exposedelectricalinterconnectsto reduceplasmainteractions

wasobservedtobecounterproductive,

resultinginincreasedarcingandtotal

plasmaleakagecurrentsforoperations

above100to 200volts.Furtherinvestigationis requiredto determine

why insulatingthe conductingsurfacescausesincreasedarcingto the

plasmaathighvoltages.

Atotalof100hoursofexperiment time

wasconductedusingthree10-squaremetersimulatedsolararraypanels

biasedup to severalkilovoltsin a

simulatedlow-Earth-orbit plasmaenvironment.Measurementswere obtainedofthefollowing:

1. Totalelectriccurrent/power loss

totheambientplasma

2. Spacechargelimitedplasma

sheathsize,development, andcurrent

limitation

3. Ion-currentfocusingby panel

high-voltagesheath

4. Transientarcdischarges

5. Effectsof insulationofexposed

conductor areaonpanelsurfaceonthe

totalcurrentleakageand arcingto

plasma

An additional20 hoursof experimenttimewasusedtoobtainsimilar

measurements usingthe0.75-squaremeterPEP(flight)solararray.Thisincluded10hourswiththearrayunder

activeilluminationat1 solarconstant.

An existing computerprogram

(PANEL)wasadaptedto allowcomputationofhigh-voltagespacecharge

sheathparametersaroundlargearrays

in a low-Earth-orbit plasmaenvironment.Thegoalis for the resulting

computerprogramto providethe

analytical partoftheplannediterative

analytical/experimental approachto

developingdesigncriteriaandcomputationalcapabilityfor designing

largehigh-voltagesystemsforusein

low Earthorbit.Applicationto test

resultsinchamberAshowgoodcorrespondencein previouslyunexplained"focusing"patternsobserved

onthelargearrays.

Figure2.BSolarillumination hasbeenturnedofftoallowlow-light televisioncamerastoview

thefaintplasmaarcing.(a)Electrical arcingtoplasmafromthePEPsolararrayat-600volts bias.Theextensivepointarcingshownresultedinnopermanent degradation ofelectrical

performance orphysical damage. (b)PEPsolararrayat+600voltsbias.Notechangeinnature

ofdischargetoawidespread corona-likepattern, ratherthanthepointdischargebhavior seen

atnegativepotentials.

49
Advanced Manned Vehicle

Onboard Propulsion Technology

The present man-rated spacecraft propulsion systems use a toxic, corrosive,

and expensive hypergolic propellant

combination of nitrogen tetroxide/

monomethyl hydrazine. For future

highly reusable manned spacecraft

propulsion systems, such as a secondgeneration Space Shuttle auxiliary

propulsion system, the hypergotic propellant combination will probably be

phased out in favor of a noncorrosive,

nontoxic, and less costly propellant

combination. Preliminary studies indicate that the liquid oxygen/hydrocarbon propellant family provides the

most attractive alternative and that an

increase in system complexity will be

unavoidable with these cryogenic propellants.

The present spacecraft auxiliary

propulsion technology data base is too

limited to allow selection of an optimum system and propellant combination. The objectives of this effort

are to identify viable auxiliary propulsion system designs and propellant

combinations to replace hypergolic

propellant systems and to develop the

technology base that will allow an orderly and cost-effective selection and

subsequent development of a secondgeneration Shuttle auxiliary propulsion

system.

Initial analytical and subscale experimental efforts will be conducted

over a wide range of operating conditions to provide basic propellant combustion and thrust chamber cooling

characteristics for promising propellant combinations. Preliminary

system design and trade studies will

involve (1) determining the inherent

design, performance, and operational

characteristics of promising propellant

combinations and system concepts,

(2) providing a common basis to compare the weight, mission performance,

cost, and operational characteristics of

promising propellant combinations

and system concepts, and (3) identifying critical areas where full-scale

component level technology efforts

would be most beneficial.

High-speed color photography of

single-element combustion has recently been used to qualitatively

characterize the basic combustion

trends of different propellant combinations and injector element designs

over a wide range of operating conditions.

Resistance-heated tubes that

simulate actual engine operating conditions have been used to characterize

the thrust chamber regenerative cooling capability of propane.

Subscale injectors of approximately

1000 pounds force will be tested to

characterize the combustion performance and stability of promising propellant combinations.

Single-Element Combustion

Photography

Liquid oxygen was tested with rocket

propellant-1 (RP-1), propane, methane, and ammonia in seven different

single-element injectors. A total of

127 hot-fire tests was conducted over

a chamber pressure range of 125 to

1500 psia. Different basic element

designs were evaluated including (1)

unlike coherent jet (fuel on oxidizer)

impingement and (2) unlike spray

(preatomized) impingement.

Striation of the propellant spray patterns (reactive stream separation) was

apparent for all of the fuels and injectors except ammonia. The degree of

reactive stream separation was observed to increase with increasing

chamber pressure, increasing fuel

temperature, decreasing unlike propetlant impingement angle, and

unlike spray impingement elements

as opposed to coherent jet elements.

The same mechanistic model developed for hypergotic propellants is

postulated to explain the trends observed with liquid oxygen/hydrocarbon

propellants. In this model (fig. 1), the

reaction of oxidizer and fuel vapors

before the impingement of the main

body of the injected propellants counteracts the hydraulic forces of the

unlike propellant streams, thus affecting the subsequent mixing process.

Subscale Combustion and Heat

Transfer

Twelve heated tube tests have been

conducted with propane. The resulting

forced convection heat transfer coefficients were 30 to 50 percent higher

than predicted. The nucleate boiling

heat flux capability of propane was

shown to be 80 to 100 percent higher

than originally predicted. Propane

coking of the inside of the heated

tubes occurred at lower wall temperatures (--500 ° F) than originally

predicted (--800 ° F).

Future efforts will include fabrication and testing of subscale injectors

and a preliminary system design and

trade study.

Figure 1 .--Vaporization-controlled liquid oxygen/hydrocarbon reactive stream separation

model.

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5O
Advanced Synthetic Aperture

Radar Technology

The 24-hour nearly all-weather highresolution features of advanced synthetic aperture radar (ASAR) provide

an Earth resources applications tool

not available with any other remote

sensor. The need for an orbiting ASAR

for monitoring of surface water, soil

salinity and moisture, vegetation

classification, ocean surface winds

and waves, and snow and ice has

been identified during several meetings sponsored by NASA. An L-band

ASAR was flown on the Seasat and a

modified L-band radar is planned for

the Office of Space and Terrestrial

Applications+l Shuttle payload.

Single-frequency ASAR with swaths

up to 100 kilometers typifies today's

technology. The envisioned ASAR

mission set for the 1980's includes

Shuttle imaging radar, Venus-orbiting

imaging radar, ice-monitoring

satellites, and Earth resources synthetic aperture radar. The functional

requirements for this mission set include swaths in excess of 150

kilometers, multifrequency, multipolarization, and multi-incidence

angle capability with amplitude

calibration to approximately 2

decibels. The purpose of this program

is to demonstrate the technology for a

multimode ASAR that can be operated

at selectable frequencies, polarizations, and incidence angles and can

generate imagery with the required

accuracy. A multimode aircraft ASAR

will be fabricated and flight-tested for

this demonstration. The system will be

parameter controlled (fig. 1) and fabricated to provide design approaches

that are flexible and automated and

that can be adopted for the anticipated missions in the 1980's (fig. 2).

This technology can also be used in

designing ASAR for spacecraft that

will satisfy multimission objectives at

substantial cost savings; e.g., Earth

resources and ocean surveys in the

same mission.

One of the goals of the the ASAR

program is to identify technology areas

for future development. Some effort

will be expended during the system

development period to study the areas

for future capability expansion including wide swath, real-time onboard

processing, pixel elevation, and complex polarization signature.

The tasks associated with the implementation of the project will be accomplished in three phases.

Phase I will consist of the following

tasks:

1. Mission requirements survey

2. System trade-off studies: multiantennas (time sharing), multibeam

scan ASAR, arrays versus reflectors,

long antennas and beam shaping,

calibration techniques, transmitter

survey, and computer simulations

3. System implementation tradeoffs

4. Multimode aircraft ASAR specification and functional design

A design document will be

developed and a formal functional

design review will be held at the conclusion of this phase.

Phase II will consist of the detailed

design, fabrication, and tests of the

system. This phase will include comprehensive design reviews to assess

the detailed design of the subsystems

prior to final commitment to fabrication.

Phase tll will consist of the integration of the ASAR system with the

aircraft and of the aircraft test flights

and data acquisition. This phase will

also include the detailed analysis of

the test flight data and the system performance assessment. A comprehensive final report will be prepared that

will include recommendations for the

spacecraft system design.

The user community will be involved in the system specification and

data evaluation phases of the project.

The ASAR was a fiscal year 1980 new

start and is scheduled for completion

in 1983. In fiscal year 1980, a survey of

Earth observation user requirements

was completed. Based on these requirements, a conceptual design was

developed. A review of technology

development was also undertaken to

survey the state of the art in subsystem

development. Subsequently, a specification document was prepared for

the system and the computer simulation program for the design verification

was updated. In addition, studies were

conducted in the area of wide-swath

transmitter and antenna design and

data processing. The detailed design

and control logic software development has begun and plans for antenna

procurement have been made.

Figure 1._arameter-controlled advanced synthetic aperture radar

system. Figure 2.--Advanced synthetic aperture radar development programs.

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51
Large Space Systems

Technology

The Large Space Systems Technology

Program is concentrating on future

space systems that are larger than the

Orbiter cargo bay and will therefore require the development of new technology, techniques, and components

to enable onorbit construction or

deployment. Some of the conceptual

requirements for large space systems

are large deployable microwave

antennas, multipurpose science and

applications platforms, and large

reflectors for missions such as the narrowband communications satellite experiment, the passive microwave

receiver, the very long baseline interferometer, and the satellite power

system test article.

JSC has been developing the overall capability to construct large

systems in space. This capability is

complementary to the space construction plans of the system as directed by

the Large Space Systems Technology

Program Office at Langley Research

Center. The activities at JSC include

platform systems studies, simulation

of the assembly of erectable structures, and subsystem technology for

automated fabrication in space.

Simulation of the assembly and

erection or deployment of space elements under zero-gravity conditions

can be performed in the Manipulator

Development Facility at JSC. From

previous platform system studies, the

following two areas for follow-on work

were identified.

Advanced Space Platform

Technology Study

A number of significant technical

issues are involved in the buildup of a

large space platform. Some of the key

mechanical problems include berthing

of the servicing vehicle or assembly

modules, handling the assembly

modules with the Remote Manipulator

System (RMS), and connecting

electrical or fluid lines between assembly modules.

The approach was to formulate requirements for mechanisms based on

platform system concepts. The platform configurations have similar

requirements for berthing platform

segments and payloads. Although

recognizing that requirements would

be limited in scope, conceptual

designs could be generated for

berthing mechanisms, umbilical interfaces, and end effectors for the RMS.

A list of berthing system requirements was derived based on Orbiter

constraints, platform interface requirements, and RMS performance. From

these requirements, the design requirements for a berthing-latch interface mechanism were generated. Six

concepts were developed and evaluated. A hexagonal frame concept (fig.

1) was designed and a full-scale functional model was fabricated for tests in

the coming year. A preliminary design

for an umbilical interface mechanism

was completed and fabrication of a

demonstration model of the adaptive

end effector is underway.

Forming and Welding of

Composite Materials

Graphite fiber reinforced thermoplastics have many desirable material

properties for the fabrication of structures in space. As well as having a

high strength-to-weight ratio and

modulus of elasticity, the material

shows very little thermal distortion.

The capability to form and join the

material is a new technology.

The approach adopted was to build

a prototype test truss from caps formed

from strip material and joined by

ultrasonic welding. Extensive modifications to an existing bench test

machine provided a forming capability. Commercial ultrasonic welding

machines were used to join the

material.

Ultrasonic welding of the composite

material was achieved with excellent

results after initial failures with

vacuum welding. The prediction was

that the commercial welder would

operate successfully in a vacuum even

though it was not designed for that environment. The welding failure was

caused by a corona effect in the

transducer and was corrected by

removing a label from the vent hole.

The effect of gravity on the weld

was evaluated by welding 45 ° and 90°

angles. Some reduction in strength

that could have been corrected by a

change in weld schedule was noted.

Cap elements were roll-formed for

the building elements of the prototype

truss. The truss was assembled on a

jig using ultrasonic welding. Valuable

data on torsional stiffness, transverse

stiffness, structural damping, and

compressive strength were obtained

in tests at JSC.

Figure 1 .---Hexagonal frame concept for the berthing-latch interface mechanism,

ALIGNMENT_

GROOVES

FRAMES

:APTURE GUIDE

IAPTUREAND

STRUCTURAL

LATCH

_LIGNMENT KEYS

ACTIVE HALF]

SUPPORT

STRUTS

52
Application of Advanced

Electric/Electronic Technology

to Commercial Aircraft

Advanced electronics technologies

similar to those used in the Space

Shuttle have potential application to

commercial transport aircraft. These

technologies include (1) redundant

digital fly-by-wire flight control and

stability augmentation, (2) comprehensive computer monitoring and

management of vehicle systems, and

(3) digital data multiplexing. Electric

actuation for aircraft control surfaces,

although not currently in use in the

Space Shuttle, is suitable for aircraft

applications as are fiber optics communication and data transmission, advanced sensor concepts such as laser

gyros, and high-voltage electrical

power systems. These advanced

electric/electronic systems are potentially more energy-efficient than current mechanical, hydraulic, and

pneumatic system designs used in

commercial aircraft. For example,

reductions in aircraft "bare-airframe"

stability can be permitted if a digital

fly-by-wire rather than a mechanical

flight control system is used. Reduced

stability requirements will, in turn,

decrease aircraft weight and aerodynamic drag, resulting in lower fuel

consumption. Also, fluid transmission

losses in hydraulic systems will increase as the size of the airplane and

length-of-line runs increase. Electric

actuation systems using high-voltage

electrical transmission offer a significantly more energy-efficient weightreducing alternative, particularly for

the large wide-body transports.

A study to define the potential payoff

from the incorporation of these advanced technologies into commercial

aircraft has been completed by the

JSC. Three types of aircraft selected

for the study included a commuter

transport weighing 28 606 pounds, a

short-haul transport weighing 40 427

pounds, and an advanced wide-body

transport weighing 459 437 pounds.

Five candidate electronic technologies that were applied to each

vehicle included digital fly-by-wire

flight control with and without reduced

stability requirements, data multiplexing, ring laser gyros, an integrated

avionics/data processing system, and

an all-electric secondary power

system. Baseline system designs were

defined for the three aircraft and

weight, cost, and reliability estimates

were made to establish a valid basis

for comparison. Preliminary designs of

the advanced technology systems

were similarly defined for each vehicle. Investment, research and technology, and operating costs of the

aircraft with these advanced systems

were then derived and incrementally

compared to similar costs for the

baseline vehicles.

The principal results of this study for

the wide-body advanced transport

aircraft (ATA) are summarized in figure

1. The net value of technology (the

difference between the cost of technology and the savings resulting from

it) and the total percent reduction in

direct operating cost for each technology are shown for the ATA with and

without reduced airframe stability.

These data are based on an assumed

fleet of 300 aircraft and a fuel cost of

S1.80 per gallon. Current industry estimates project fuel prices between S2

and S3 per gallon in the early 1990's.

As can be seen in figure 1, the allelectric secondary power system ATA

shows the highest cost savings, totaling more than S9 billion over a 16-year

period. This is a large payoff and supports further work by NASA in the

development of these technologies for

aircraft applications. The benefits,

when realized, will result in higher

productivity for the airplane industry,

lower airfares for the passenger, and

significant energy savings for the

United States. A contractor's report,

"Application of Advanced Electric/

Electronic Technology to Conventional

Aircraft," summarizing the results of

this study has been published.

Figure 1.--Net value of ATA technology.

SAVINGS

S-BILLIONS

10.0

8.0

6.0

4.0

2.0

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STATIC STABILITY

EJ FUEL

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AND INSURANCE

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4.0 COST

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53
Nonterrestrial Materials for

Space Use

Future space activities may involve the

construction of very large structures in

space. Because significantly less

energy is required to launch materials

from the Moon than from the Earth,

these large-scale space activities may

benefit from the development of

manufacturing industries in space that

obtain the bulk of their raw materials

from the rocks and minerals of the

Moon. Two activities have been completed and a third has been

redirected.

Handbook of Lunar Materials

The physical and chemical properties

of lunar rocks, soils, and minerals are

basic data needed for feasibility and

design studies of advanced processes

for refining lunar materials. This need

has been filled by the preparation and

publication of a document, "Handbook

of Lunar Materials." It is available as

NASA Reference Publication 1057.

Nonterrestrial Materials for LargeScale Space Construction

Large-scale construction activities in

space might benefit if metals,

ceramics, glass, and other materials

could be produced from lunar rocks

and soils. These potential resources

present significant technical challenges, particularly in the area of refining. The low-grade and nonspecific

nature of these "ores," the necessity

to close all chemical cycles, and the

desire to construct chemically efficient processes that produce as much

as possible from as little as possible

are the sources of these technical

challenges. The focus of this study has

been the definition of the chemical

and physical processes that could be

used to produce construction materials

from lunar "ores."

Prior efforts concentrated on the

quantification of the mining and ore

beneficiation processes and on the

screening of various chemical processes for refining lunar materials. A

fluorosilicic acid process (fig. 1) that

Figure 1._chematic diagram showing the major process elements and flows in the

fluorosilicic acid process proposed for use in refining lunar materials.

...... -f ......... 7

I

I

I

I

I

uses hydrolysis and electrolysis to

separate and concentrate the products

from refining dilute ores was developed. The study results are presented in a contractor report, "Extraterrestrial Materials Processing and

Construction."

The fiscal year 1980 efforts were

directed toward (1) preparing a more

detailed design and definition of the

fluorosilicic acid process, (2) holding a

workshop on applied electrochemistry, and (3) determining the use of

products and intermediaries in the

fluorosilicic acid process for ceramic

manufacture. The study results,

workshop reports, and all technical

papers are included in the contractor

report.

Refining of Nonterrestrial Materials

Although processes used to extract

useful materials from lunar ores may

be defined on paper by using thermodynamic and engineering computations, the actual viability of a process can only be tested in the laboratory. Two aspects of such testing have

been explored this year.

The first aspect relates to the

extraction of oxygen by hightemperature electrolysis of gaseous

process effluents, especially the extraction from carbon dioxide, which is

an effluent from some types of refining. Previous research has shown that

thermal decomposition followed by

oxygen pumping across the solid

electrolyte appears to be the limiting

step. Therefore, a new test design that

permits the use of ultraviolet light

stimulation has been designed and

built. Tests are planned for the fall of

1980.

The second aspect relates to the

definition of the dissolution and phase

separahon steps of the fluorosilicic

acid process (fig. 1) in terms of experimental variables. The process steps

were mapped onto a pF-pH diagram

and compared with known solubility

data. These were then reduced to a

hierarchical set of unknowns that need

to be specified to define the process

better. A set of alternates for the process elements was also defined as

were figures of merit. An in-house

status report of the results is available.

54
Fire-Resistant Low-SmokeGenerating Thermally Stable End

Items for Aircraft and Spacecraft

The general objectives are to apply

fire-resistant materials technology to

crash and ramp fires in commercial

aircraft and to conduct systems testing

of new and modified fire-resistant

materials in configurations such as

aircraft lavatories, galleys, seats,

fuselage sections, and the general

cabin area. The basic objectives of the

program are as follows:

1. To demonstrate that the introduction of fire-barrier materials in

the exterior wall will prevent an external "design" fire from entering closed

and intact habitable areas for the

minimum 5-minute period needed for

passenger evacuation

2. To demonstrate that a closed

and intact cabin will not reach a temperature of 400 ° F (considered a lethal

temperature level for humans) nor

contain smoke or toxic gases at temperatures up to 400 ° F for a specified

"design" fire

3. To demonstrate that a "design"

fire in the area of a cabin opening will

not propagate throughout the cabin

area during the minimum 5-minute

period

The program was initiated to identify,

develop, and characterize fire-resistant materials to meet the spacecraft

flammability specification requirements of the Federal Aviation Administration, the aircraft manufacturers,

and JSC. A fire-retardant rigid polyimide foam system was developed for

internal applications. Using this technology and expanding the program to

include other applications, significant

progress was made in developing fireresistant low-smoke-generating thermally stable polyimide end items.

tion of the foam is expected by early

summer 1981. The latest formulation

of the resilient foam has the lowest (90

percent) compression set. It has been

tested by a prime aircraft seat

manufacturer for indentation load

deflection and processability and was

found satisfactory. The vendor has

now requested two different densities

of the seat foam to make several passenger seat backs for flight tests. This

resilient seat foam has also been sent

to another prime aircraft seat manufacturer for fabrication into prototype

seats to be fire tested by two research

centers.

The recent advances in the polyimide

resilient foam technology resulted

from increasing the power in the 6- by

6- by 12-foot microwave oven from 15

to 20 kilowatts. This power increase

permitted production of large-size

foam "buns" and also accomplished

foaming and curing in one process. In

addition, the spray-drying time for the

base resin has been reduced from 18

hours to 30 minutes and the quantity of

resin produced has been increased to

39 pounds per day.

Formulations of polyimide thermalacoustical foam insulation incorporating 20 percent milled fiberfrax fibers

did not shrink in length or width but

ablated in thickness without burnthrough and gave a satisfactory firebarrier time. The acoustical properties,

however, were not met. A newly

developed Fluorel/fiberglass laminate

did meet the acoustical requirements and also showed promise as a

wallboard. The combination of

Fluorel/fiberglass laminate and

polyimide foam as the thermalacoustical insulation in a wallboard

will be tested for effective thermalacoustical fire-barrier properties.

Multiple-density foam wallboards still

require further development in the

area of edging compounds with good

screw-withdrawal properties before

they can be produced commercially.

Two rigid polyimide-foam-filled honeycomb floorboards with improved

adhesive to bond the face sheets are

being fabricated for functional testing

in a 747 jet aircraft. A previously installed panel failed after 2633 hours

because the face-sheet bond was

inadequate.

The aircraft fuselage panel burnthrough test program was modified to

fabricate and test standard wide-body

jet aircraft fuselage sections. These

will be tested over a pit of burning fuel

previously calibrated to give a burn

time of specific length and thermal

output. The jet fuel characterization

fire for these tests is shown in figure 1.

The test stand includes an instrumented stainless steel panel used to

calibrate the jet fuel quantity for a burn

time of specific length and thermal

output. If the wide-body jet materials

perform satisfactorily, these materials

will be fabricated in a narrow-body jet

aircraft fuselage panel and retested.

Figure 1.---Jet fuel characterizationfire.

Concurrent with the polyimide

developments, a program was formulated to fabricate 8- by 12-foot aircraft

fuselage section panels using

baseline and advanced materials and

to test them for burnthrough properties

over a pit of burning jet fuel simulating

a postcrash fuel fire.

Fire-resistant low-smoke-generating resilient seat cushion polyimide

foam is available in laboratory quantities for flight tests. Pilot plant produc55

t
Toxicity Testing and Evaluation

of Candidate Aircraft Materials

Each year in the United States, thousands of lives and millions of dollars in

property are lost by fire. To reduce this

loss, new fire-resistant materials and

chemical additives have been

developed that significantly reduce

the flammability of conventional

materials. Recent evidence, however,

indicates that materials containing

fire-retardant additives may produce

severely toxic gases in a fire. These

gases could be extremely critical

because of their potential to induce

behavioral incapacitation and thus

prevent escape. Therefore, the

screening of materials for fire safety

has been expanded to include not only

tests of flammability but also of

behavioral toxicity. A major difficulty

facing material manufacturers is that

there is no standardized test for

behavioral toxicity.

As a part of NASA's fire-retardantmaterials engineering program (FIREMEN) at JSC, operant behavior technology has been used in the toxicity

testing of aircraft cabin materials. A recent experiment illustrates how this

technology could be employed in the

screening of materials for potential

toxicity.

Small uniform samples of either a

conventional fire-retardant polyurethane or a newly developed polyimide

foam were pyrolyzed at three different

temperatures in a chamber housing

test animals trained to press a lever to

terminate brief electric shocks (fig. 1).

During each pyrolysis test, air samples

were withdrawn from the chamber and

analyzed for carbon monoxide and hydrogen cyanide. Throughout the test,

the lever-pressing behavior of the

animals was monitored by computer.

To ascertain the relative toxicities of

the two polymers, the behavioral

effects induced by their pyrolysis

products at each temperature were

compared and analyzed.

The results of this experiment indicated that the behavioral toxicity of

these two polymers varied differentially with pyrolysis temperature. At

the lowest temperature, the greater

resistance of the polyimide foam to

thermal decomposition resulted in

lower off-gas concentrations and consequently in fewer behavioral effects.

At the highest pyrolysis temperature,

just the opposite effect was found.

These results help to identify some of

the complexities involved in ranking

materials according to potential

behavioral toxicity. The ranking of

these two polymers based only on

either the high or the low pyrolysis

temperature would not have been

accurate.

In addition to the behavioral toxicity

tests of these polymers, the JSC

FIREMEN program has included (1)

comparisons of the susceptibility of

different behaviors to toxic incapacitation, (2) full-scale fire tests of materials in a 737 fuselage, and (3) comparisons of full-scale and laboratory

toxicity tests.

Figure 1 .--Experiment setup to test pyrolysis toxicity of candidate aircraft materials.

56
Adsorption Pumping Cryogenic

Refrigeration

The objective of this project is to

develop and demonstrate operation of

a new type of cryogenic refrigeration

called the Molecular Adsorption

Refrigeration System (MARS). The

device (fig. 1), which uses an adsorption pumping cycle, is nonmechanical

(has no moving parts) and will provide

a highly reliable source of cryogenic

cooling. This cooling could be

cryogenic cooling for long-wavelength

infrared detectors for long-term orbital,

deep space, or aircraft missions. This

system could also provide conventional cooling for spacecraft and/or terrestrial uses such as automotive air

conditioning where waste heat could

be the power source.

The adsorption pumping cycle is similar to the better-known liquid absorbent cycle that makes use of the ammonia absorption properties of water.

In the liquid absorbent cycle, the application of heat to the mixture

releases the ammonia through an expansion valve and lowers the temperature. Conversely, the MARS cycle

uses a mineral called zeolite (also

called molecular sieves) that has a

crystalline structure with storage

cavities that electrostatically attract

charged gas molecules to the inner

walls. The refrigerant is subsequently

driven out of the zeolite and pressurized by the application of heat,

which may be waste heat or solar

energy. Expansion through a JouleThomson valve liquefies the gas and

produces cryogenic temperatures.

Closed-loop and continuous operation

is effected by the use of other containers of zeolite, one of which adsorbs the cooled refrigerant while

another is preheated to be switched in

when the gas is exhausted from the

container in use.

The Molecular Adsorption Refrigeration System is capable, in the current

design, of producing 5 watts of cooling

power. To date, principles of operation

and attainment of goals have been

demonstrated in the laboratory using

an engineering evaluation model that

is the culmination of the development

effort. This model, the design of which

is based on the theory and the models

developed in the course of the work,

provides proof of the Molecular Adsorption Refrigeration System concept

and the availability of valuable design

tools for future effort. A limited amount

of investigative work has also been

accomplished using a naturally occurring zeolite, called mordenite, as opposed to the original synthesized

zeolite. The apparent superior properties of the new zeolite, along with the

verified theory, mathematical model,

and experimental insights gained in

the accomplishment of the project,

will permit significant increases in

performance with corresponding

decreases in power, weight, and

volume of future designs. This system

will be evaluated as a potential airconditioner for automobiles using

waste heat from batteries or from an

internal combustion engine.

Figure 1 .--Schematic diagram of a two-stage nitrogen liquefier using adsorption pumping.

-RMOELECTRIC HEAT

PUMP

ZEOLITE ZEOLITE NITROUS OXIDE

STAGE ADSORBER

AND DESORBER

NITROGEN

ADSORBER

COOLING

CIRCUIT_

(HEAT SOURCE '

FOR DESORBING

NOT SHOWN)

REGENERATIVE

HEAT EXCHANGER

SECOND STAGE

HEAT SINK

EOLII"E 1 _ZEOLITE _

tt EGENERATIVE HEAT

_> EXCHANGER

LN2--'-I-_ :3 WATT LOAD

(_ SOLENOID

VALVE

@ CHECK VALVE

NITROGEN SECOND

STAGE ADSORBER

AND DESORBER

57

Office of

Space and

Terrestrial

Applications

Significant Tasks

61

64

66

68

7O

71

72

Forest Resource Information System

Funded by'. Resource Observation, Applied Research,

and Data Analysis (UPN-677)

Project Manager: R. E. Joosten/SH2

Task Performed by: Purdue University Laboratory for

Applications of Remote Sensing

Contract NAS 9-15325

AgRISTARS: Supporting Research Project

Funded by: Resource Observation (UPN-691)

Project Manager: William E, Rice/SA

Task Performed by: NASA, U,S. Department of Agriculture,

and U.S. Department of Commerce

AgRISTARS: Foreign Commodity Production

Forecasting Project

Funded by: Resource Observation (UPN-691)

Project Manager: William E. Rice/SA

Task Performed by: NASA, US. Department of Agriculture,

and U.S. Department of Commerce

Wildland Vegetation Resource Inventory

Funded by: Resource Observation, Applied Research,

and Data Analysis (UPN-677)

Project Manager: K. J. Hancock/SH2

Task Performed by: ESL Corporation

Contract NAS 9-15740

Texas Natural Resources Inventory and Monitoring System

Funded by: Applications Systems Verification Test (UPN-658)

Project Manager: Leo ChildstSK

Task Performed by: Lyndon B. Johnson Space Center

Lockheed Electronics Company, Inc.

Contract T-6984G

Orbiter Camera Payload System

Funded by: Shuttle Experiments (UPN-666)

Technical Monitor: B. H. Motlberg/ED8

Task Performed by: Itek Optical Systems Division

Contract NAS 9-15671

Extended Scene Radar Calibration

Funded by: Resource Observation (UPN-677)

Technical Monitor: R. G Fenner/ED6

Task Performed by: Lyndon B. Johnson Space Center

59
73 SIR-A Antenna Integration to OSTA-I Pallet

Funded by: Resource Observation (UPN-666)

Technical Monitor: Harold Nitchske/ED6

Task Performed by: Lyndon B. Johnson Space Center

Ball Brothers Aerospace Corporation

Contract NAS 9-15512

60
Forest Resource Information

System

The Forest Resource Information

System (FRIS) was initiated as an Application Pilot Test in October 1977 to

demonstrate and verify the utility of

Landsat computer-aided classification

technology to industrial forest management problems in the Southeastern United States. The primary

goal was to implement and establish

an independent operational information system in which Landsat data is a

viable component and also to determine if space technology is financially

attractive and easy to use and can

maintain the confidence of management for operational functions by an

industrial user. The Southern Timberland Division of the St. Regis Paper

Company owns or controls over 2.3

million acres throughout Florida,

Georgia, Alabama, Mississippi, Louisiana, and Texas (fig. t ). By participating with NASA in the Application Pilot

Test project, St. Regis made a

philosophical and fiscal commitment

to share in the overall management

responsibility and in the total cost to

implement such a system.

A cooperative agreement between St.

Regis and NASA is the instrument of

record that defined the responsibilities

of both parties. NASA shares in the

project management by providing for

the contractual support (the Laboratory

for Applications of Remote Sensing

(LARS) of Purdue University) to

develop specific quantifiable forest

resource information from Landsat

multispectral-scanner (MSS) data and

correlate this to the inventory data furnished by St. Regis on specific test

sites. The contractor wilt develop

classifications analysis procedures

and software and provide for the technical training of St. Regis project personnel. NASA will also provide for the

technical coordination of St. Regis and

contractor project personnel during the

four-phased project (fig. 2).

The technology developed for this

project will be documented and

transferred into the public domain for

possible use in the wood products industry. St. Regis will also furnish a final

report on the usefulness of the system

and a cost and benefit analysis study.

The past year established several

highlights: (1) the transfer of the

LARSFRIS software to a St. Regis computer system, (2) the establishment of

the FRIS Center in Jacksonville,

Florida, by St. Regis, and (3) the implementation of the FRIS design as established by the project.

The LARSFRIS software was

transferred to the St. Regis National

Computer Center in Dallas, Texas.

This software consisted of two main

elements: the LARSYS preprocessing

software and the classification programs for the analysis of remote-sensing data. The preprocessing programs

consist of three major processors.

These processors convert the standard

Landsat MSS digital tapes to a LARSYS format, perform systematic

geometric corrections, and provide the

capability to register temporal scenes

of Landsat data sets and to register the

Landsat data to a map base.

Figure 1.----Landholdings of the Southern Timberland Division of the

St. Regis Paper Company.

LAND HOLDINGS - 2.3 million acres

"t _L

TEXAS :i MISSISSIPP_ '_ GEORGIA

3 !

:'" ' _'_ " ALABAMA ,

• , rj

,, LOUISIANA *, : FLORIDA . _L_,,- _,

_ ..... ._- -_ _,,.

J _,_ ,:ip_ 1 LO_ER COASTAL PL_._N h

2 MIDDLE COASTAL _LAIN i "\\

3 UPPER COASTAL PLAIN,'PIEDMONT ]

AtLUWAL BOTTO_ LANOS _'

ACRES LAPPROi i ' 4"_ ,j

1 2_S 00D _

_00oe

_o oDD

Figure 2.--The four phases of the St. Regis Project.

I All ]I-TECHNIOUES

DEVELOPMENT

LANI)SAT

TECHNOLOOY

• DEMOI,_rRATE _

SYSTEM :_

• EVALUATE i

COST

INDU8TRIAL

FOREIrrRY

PHASE H

IMPLEMENTATION

PHASE _r

FOREST

RESOURCE

INFORMATION

SYSTEM

LANDSAT DATA i I

ANALYSIS

I !

61
A totalof 20processingfunctions

has beentransferredto the Dallas

facilityforconvertingLandsatdatainto

informationusefulformonitoringand

inventoryingforestresources(figs.3

and4). ThisimageprocessingsubsystemcomprisesasubsetoftheLARSYS3.1-versionsoftwarepackagethat

currentlyresidesinNASA'sComputer

SoftwareManagement and InformationCenter(COSMIC)of theUniversity of Georgia,the LARSYSDV

(development) modules, andtwonew

functionsdevelopeduringthisproject.Thetotalsubsystem, whichwill

be identifiedasLARSFRIS, wasconvertedtooperateontheSt.RegisIBM

3033system.

In January1980,the St. Regis

PaperCompanyprovidedtheofficial

acceptanceof the projectdemonstrationphase.Thisactionprovided

thenecessarycapitalexpendituresto

implementtheFRISin a production

modein the SouthernTimberlands

Division.InApril1980,theSouthern

TimberlandsDivisionestablishedthe

FRISCenterin Jacksonville, Florida.

TheFRISCenter'sobjectivesareto

completethe developmentof the

system,to implementi onanoperational basis,and to maintainand

enhancethetotalresourceinformation

systemtomeettheneedsof thedivision.

Figure 3..--Landsat forest-type map of St. Regis Paper Company, Fargo, Georgia, Test Area,

prepared in 1979 from 1976 data.

COLOR CODE CLASS LEGEND

RED I PiNE

PINK MIXED YOUNG PLANTATION

CLEAR CUT

[)ARK BLUE I PURE CYPRESS PONDS

LIGHT

BLUE SLASH PINE CYPRESS STANDS

GREENTAN R BOTTOM LAND HARDWOODS

WHITE _ NOT DWNED BY ST REGIS

. "- t

4 ADMINISTRATIVE UNITS

Figure 4.---Example of a change map showing the areas that changed between the 1977 and

1979 classifications.

0 0 1 1 2 2 2

4 8 2 6 0 4 8 CLASSES

0 0 0 0 0 0 0

_ _ _ _. _ _ I 4. _ 4, _ _ _ 4, ANY CLASS CHANGE

080 -_ _'_R TO NONSTOCKED

120 *

160 *

200

240.

NONSTOCKED

SAME BOTH DATES

LOW DENSITY PINE__

SAME BOTH DATES

PINE AND

SLASH/CYPRESS

SAME BOTH DATES

MIXED PINE/HARDW00D

SAME BOTH DATES

360 *

440 -'

480 *

1 f t t 1" "r _ I 1"

0 1 1 2

8 2 6 0

0 0 0 0

1 1"

2

4

0

NONSTOCKED TO ANY __

VEGETATION

1" 1" I"

2

8

0

62
The FRISwill havethreemajor

components(fig.5) basicallyrepresentingtheinvolvement oftwomajor

technological advances.Theimageprocessingsubsystemrepresentshe

roleofsatelliteremotesensingfordata

collection, land cover analysis,

monitoringof changesof forest

resources, updateverificationandinputsto landacquisition,long-range

planning,and forestinventory.The

secondsubsystemis a new computerizedmappingcapabilitytoestablishthedatabaseandreviseandupdateforestresourcedatamapsandis

an interactivemethodologyto merge

digital-,polygon-, andtabular-typeinformationtoproduceoutputproducts.

The third subsystemconsistsof

descriptiveinventorydataandsimulationandplanningmodelsthatwere

alreadyestablishedbySt.Regisand

arenowpartof thetotalinformation

system.

Newhardwarepurchasedby St.

RegisfortheJacksonvillecenterincludesaminicomputer forintegrating

inventory,map,and satellitedata

bases.Theminicomputer willaccommodatelocalusersandserveasaterminaltothecomputercenteratDallas.

Theminicomputerwill alsosupport

futureremotegraphicstationswithin

the SouthernTimberlandsDivision.

The interactivegraphicsterminal

clusterconsistsofadigitizingtableto

establishandupdatemapdatafiles

andtwocathode-raytubestobeused

forediting,manipulation, anddisplay

ofmapandtabularinformation. Adrum

plotterwill be used as an output

mediumfor all mapsanddrawings.

Also,a color-imagedisplaywill be

usedasaninteractivedeviceforLandsatregistrationactivities,classification

analysis,anddisplayofresultsincluding a mapoverlaycapability.Additionalequipmentincludesalphanumericterminalsanda lineprinter.

TheIBM3033computerinDallas

willprocessmostof themoretedious

applicationsina batchmode,andthe

systeminJacksonvillewillprovidethe

interactiveinterfaceforthedatamanagementandretrievalfunctions.Most

of the basicinventoryandplanning

modelsthatusesimulationandlinear

programingtechniquesare on the

Dallassystemandwill becompletely

compatiblewith theLARSFRISsoftware.Thetotalsystemwill perform

variousfunctional activitiesandwillbe

a dynamiceasilyaccessiblemanagementtoolformeetingoperational requirements.

Documentationof the software

transferredbyLARStoSt.Regiswill

be availablethroughCOSMIC.Final

reports,currentlyin progress,from

LARSandSt.Regiswillalsobeplaced

inthepublicdomain.InMay1981,St.

RegisandNASAwillconductaSpace

TechnologyandIndustrial ForestManagementconferencein Jacksonville,

Florida,to presentheFRISApplicationPilotTestconceptanddiscussits

attractivenessto privateindustryfor

managingforestresources.

Figure5.---Forest ResourceInformation System.

I

LIMAGE-1

PROCESSING

SUBSYSTEM

rFOREST RESOURCEINFORMATION SYSTEM]

I

,NTERACT,VEI

MAPPING I

SUBSYSTEM J

i

iNVENTORYANDl

TABULAR DATA I

SUBSYSTEM J

• LANDSAT

PREPROCESSING

• CLASSIFICATION AND

MENSURATION

• POST PROCESSING

CONVERSIONTO

IMAGE VECTORS

• MAP DIGITIZING

• MAP INTERACTION

• WINDOWING

• SCALING

• SHADING

• CREATION OF

DIFFERENT

BOUNDARYLAYERS

• POLITICAL

• CADASTRAL

• OWNERSHIP

• OPERATINGAREA

SUMMARIES

• VOLUME/GROWTH

INFORMATION

• SITE INDEX

• BASAL AREA

• ETC.

63
AgRISTARS: Supporting

Research Project

The Supporting Research project is

one of eight projects in the

AgRISTARS Program. The purpose of

the project is to provide an integrated

research effort that supports several

other AgRISTARS projects. Directly

supported are the Foreign Commodity

Production Forecasting, the Early

Warning/Crop Condition Assessment,

and the Yield Model Development projects. Indirect benefits accrue to the

Domestic Crops and Land Cover, the

Soil Moisture, and perhaps the

Renewable Resources Inventory projects. The Supporting Research project continues the previous focus on

techniques related to production

estimation of wheat, barley, corn, and

soybeans in foreign regions with

planned extensions to rice, cotton,

sorghum, and sunflowers in future

years; the project also contains

enhanced efforts in agronomic remote

sensing.

The technical effort in this project is

divided into the following areas.

1. Area estimation research: includes machine processing, manual

processing (labeling/image interpretation), and preprocessing (image

registration and image display)

2. Agronomic remote sensing: includes crop development stage

estimation and spectral inputs to yield

estimation

3. Supporting field research

The area estimation research plan

includes the development of technologies for estimating crop proportions in small (5 by 5 mile) segments

of Landsat multispectral-scanner

(MSS) digital imagery, for estimating

crop proportions in larger areas such

as Landsat MSS full frames, and for

segment estimates in Landsat D

thematic mapper data. Currently, active research is aimed at the MSS fullframe estimation; research on use of

thematic mapper data is at a background level but a substantial effort'

will begin in fiscal year 1981.

Many crops appear spectrally similar in Landsat MSS data at a given

point in time; separations of these

crops are only possible by use of

multidate sequences of MSS imagery,

which allow individual crops (e.g.,

64

wheat) to be recognized on the basis

of their temporal spectral development. Even this approach, which was

the basis of the Large-Area Crop Inventory Experiment (LAClE) efforts,

does not allow lO0-percent accuracy

in crop recognition, both because of

the significant overlap of the individual

crop temporal spectral development

patterns ("signatures") and because

of the visibility in crop signatures due

to such factors as planting date,

variety, and weather. The approach to

this problem has been predicated on

the following judgments.

1. The requirement to assess the

crop identity at a sufficiently large

number of locations to make an accurate estimate of crop proportions cannot possibly be done economically

unless it is automated.

2. The current lack of quantitative

understanding of how crop signatures

are affected by external factors requires the .use of a human analyst to

adjust the parameters of ("train") the

automated processing system to the

local conditions.

In practice, the analyst has

manually identified ("labeled") training samples from the Landsat image to

be machine processed. Several important accomplishments in this area

have occurred in the past year.

Previously, machine processing has

been used primarily to reduce the error

in an analyst-based estimate because

the analyst cannot economically identify all pixels in the Landsat MSS image ("sampling variance") while propagating the effect of other analystinduced errors. In the past year,

however, several machine processing

approaches have been identified in

which other analyst-induced errors are

substantially attenuated. The first such

technique has been delivered to the

Foreign Commodity Production

Forecasting project. All these techniques have been enabled by the previous development of computer

algorithms capable of automatically

isolating and characterizing the

statistical crop signature distributions

present in a segment of MSS data.

Further improvements in this area are

anticipated.

Analysis of multidate MSS data has

been a cumbersome process for

several reasons: (1) Each Landsat observation contributes four distinct

measurements on each pixel, (2)

different segments of data have

different acquisition histories, and (3)

variations in planting date from field to

field cause substantial variations in individual crop signatures on each acquisition date. Simplified representations of multidate MSS data that offer

new insights into the crop identification and assessment process, substantially reduce the cumbersomeness

of the data, allow us to eliminate the

planting date influence, and reduce

the sensitivity to acquisition dates (fig.

1) have been developed. These techFigure 1.--Multidate multispectral scannerdata. O's andX's are Landsat observations on overpass dates. (a) Typical crop profile. (b) Variations due to planting date, (c and d) The effects of

shiftingall observations to a single crop emergence date.

c.O

W

Z

I.IJ

W

(a)

I.l.J

z

z

I.iJ

t_

(c)

i i _ i i i

DAY OF YEAR

I I d'l [ I i l t i | I I I l

DAY OF YEAR

O'3

_3

Z

Z

LU

I,Ll

(.0

(b)

,,/3

,..,"3

I.LI

z

z

L.U

(d)

Ii_ i i

DAY OF YEAR

V 0

X

X V

¥ j° I

I I I J J J I ! J l I I I

DAY OF YEAR


niques are regarded as being the foundation of a probable breakthrough in

MSS processing in that it will be possible to characterize a crop by

agronomically meaningful descriptions (e.g., planting date and growingseason length) rather than by a sequence of MSS observation values.

Previously, the labeling process has

been a highly labor-intensive process

in which the analyst has been called

upon to make not only those decisions

which he is uniquely qualified to make

but also a large number of relatively

mundane decisions. Many of the more

mundane have become sufficiently

quantitative to enable their automation

in the labeling procedure. This will

have the major advantages of both

reducing the cost of labeling and making it possible to objectively study the

effect of variations in the labeling process.

In LACIE, registered multidate MSS

data were provided by the Goddard

Space Flight Center LACIE processor.

This system, which provided registration to a 1974 state-of-the-art value of

1 pixel rms (a marginal value for many

of the applications), is now being

phased out. The technical design of a

new JSC registration system that will

replace the LACIE processor and provide the foundation for a sequence of

improvements in registration accuracy

has been completed.

In LACIE and in the Multicrop

Research Program, research was

largely concentrated on crop area

estimation techniques, with a

relatively low level of research

directed at agronomic remote sensing

through fiscal year 1980. A major goal

of the Supporting Research project is

to advance the state-of-the-art technology in agronomic remote sensing to

a quantitative rather than qualitative

level; resources directed to this area

will be substantially increased in fiscal

years 1981-85. Despite the limited

level of resources in fiscal year 1980,

two significant accomplishments have

occurred. The first was the discovery

that, at least for corn and soybeans,

the crop development stage is closely

related to the accumulated versus the

projected area under the crop

development curve and that we could

project backwards in time along the

crop development curve to determine

the emergence date (fig. 2). The importance of this is twofold: (1) when

the spectrum of the crop development

stage can be measured, rather than

simply estimated from meteorological

or historical data, the performance of a

meteorologically driven yield model

can be substantially improved; and (2)

the crop development stage models

can now be run on a per-field basis to

improve the accuracy of labeling. The

second significant accomplishment

was the conceptual development of an

advanced yield model in which MSS

data are used to determine the crop

leaf area index and, hence, the fraction of incident sunlight intercepted.

This yield model would be combined

with Metsat (meteorological satellite)

measurements of insolation to derive

solar inputs required by process-level

yield models (fig. 3).

The remaining major technical area

in the Supporting Research project is

supporting field research, which conducts experiments involving the acquisition and analysis of data sets containing both spectral and agronomic

measurements, frequently under conditions of controlled variability. Major

recent accomplishments include (1)

an experiment that shows the effects

of various factors (e.g., row width, row

direction, solar elevation angle, and

soil color) on corn and soybean reflectances, and (2) the development of a

low-cost radiometer system that will

permit substantial expansion of the

supporting field research program

without an equivalent cost increase.

In summary, the first-year 1980

effort in Supporting Research has

resulted in substantial technical

progress and has placed the Supporting Research project in a good position to initiate the work to be performed in subsequent years.

Figure 2..--Spectral profile crop development stage estimation.

40

30

L.,

2o

w

10

BEST FIT

CURVE _ 5_'_, z_ GREENNESS

/ _5/MEASURE OVER

5/_ FIELD NO. 5

5\ 5f _- STANDING RIPE

BARE B

SOIL 5 I \_

LINE ----_ / 'l EXTRAPOLATION

_TO BARE SOIL

- -5 _ 5._./_ -- .u

CROP 5 ........_I,

EMERGENCE_ f ESTIMATION

DATE _I DATE

T-,ERO,--.J 0 I I I I l J

40 80 120 160 200 240 280 320

TIME (CALENDAR BAYS)

• CROP DEVELOPMENT STAGE IS LINEARLY RELATED TO

AREA A

AREA A AND B

Figure 3.--Remote sensing inputs to yield models.

i / _ II

iI _ ii

i

CORN

o 3 6 9 _z _5 _o

R_FLeCIANCe L% 06 to o ;,

STATUS, ACCOmPLISHM[NTS IO DATE

• COnCeptUAL _pPRC_CH

• _E_O UEV(L _St_BL_SHM_N_

OF POt EN_AL

65
AgRISTARS: Foreign

Commodity Production

Forecasting Project

The Foreign Commodity Production

Forecasting project of AgRISTARS

builds on 6 years of joint experience

by the U.S. Department of Agriculture,

NASA, and the National Oceanic and

Atmospheric Administration in foreign

crop production forecasting and

remote-sensing research and

development and on more than 15

years of crop-related aerospace

remote-sensing technology in the

United States. Previous triagency

research of the application of Landsat

multispectral-scanner and weather

data has established a suitable basis

for the Foreign Commodity Production

Forecasting project (fig. 1). For example, previous accomplishments have

(1) shown that regression-yield

models for wheat have worked well

under both average conditions and

under important conditions that significantly departed from the average;

(2) shown that small grains can be

reliably estimated in important areas;

(3) demonstrated the value of exploratory experiments in foreign areas

to identify each region's unique commodity characteristics in addition to

research in the United States where

detailed ground truth is available; (4)

provided understanding of real problem areas, quantified their impact, and

developed generalized approaches for

their solution; (5) provided an understanding of the need for improved

spectral, spatial, and temporal resolution of satellite sensors and systern_:

and _'_ ohown that data loads ass,.,,..;-

_,,..u wan the technology can be

handled. In addition, at the outset of

the AgRISTARS, the Foreign Commodity Production Forecasting project

has the following advantages of previous research:

1. Teams of scientific personnel experienced in this technology and its

application within the participating

agencies

2. Universities and industries that

can now perform a more significant

role in research and development

3. In-place research and development data systems

4. Existing data bases that will

allow the effective use of retrospective

data in the development and evaluation of technology over many of the

crop regions to be investigated

5. Components of technology that

will serve as building blocks for further

research

Figure 1 .--Spectral separability of corn and soybeans, Pottawattomie, Iowa, 1978.

POTTAWATrOMIE, IOWA 1978

.41,_

<,I

LU

LU

LANDSAT MSS DATA IDENTIFICATION

_SJULY

23 JULY ._

• i

CORN SOYBEANS

31 JULY

-- m

SEPT

::,

i

SEPT

8R_HTNESS

6. The considerable research

already conducted by LACIE and the

LACIE Transition Project to isolate the

wheat/barley/small-grains issues and

effect solutions

7. Experience in development of

corn and soybeans technology based

on the Corn Blight Watch Experiment

8. The Crop Identification Tech-

_utogy Assessment for Remote Sensing (CITARS) experiment over Illinois

and Indiana

9. The USDA research in Illinois and

Iowa

10. An 18-month experiment during

fiscal years 1978 and 1979 over the

US. corn and soybeans belts

The Foreign Commodity Production

Forecasting project will build upon the

technical capability of this previous

research to further advance the applications of remote sensing to foreign

production forecasting through

research and development. It will be

test oriented toward resolving the remaining issues in direct observation of

wheat and barley in the presence of

other small grains; extending the technology to additional crops and regions;

using improvements in spectral,

spatial, and temporal characteristics of

satellite sensors such as the sevenband 40-meter-resolution Landsat D

thematic mapper; developing improvements in early season production

estimation technology; developing approaches that tend to be more costeffective; and quantifying the value of

still further improvements in the technology (e.g., sensors, crop identification, pattern recognition, registration,

etc.).

66
I

The scope of this project involves

wheat or barley or both over selected

regions within Canada, U.S.S.R., India,

Australia, and Argentina; corn and soybeans over selected regions within

Argentina and Brazil; beginning technology extension to rice in India; and

exploratory investigations in the

United States for cotton, sorghum, and

sunflowers. Production estimation

technology will be developed and

evaluated for each crop and region

combination. Technique development

and problem solving will be carried out

in "similar" US. crop regions (where

good ground truth is available) in

parallel with the foreign crop regions,

where independent data and statistics

are not as timely or reliable. The

quality and availability of government

statistics vary from country to country

and from region to region within a

country. Assessment of achievable

performance in foreign regions will depend on the performance assessment

in similar U.S. regions as well as comparison to independent foreign estimates.

AgRISTARS during fiscal year 1980

continued those activities that were

carried out in the LACIE Transition Project. In particular, efforts were continued on advancing techniques to

perform crop identification and

classification on corn and soybeans

and wheat and barley. During the fiscal year, the supporting research and

technology community, primarily the

Environmental Research Institute of

Michigan (ERIM) and the University of

California at Berkeley (UCB), was

given the major role in corn and soybeans classification technology and

the JSC Earth Observations Division

assumed the lead in wheat and barley

technology.

At JSC, the principal classification

effort was to translate transition-year

corn and soybeans crop identification

and classification techniques into

wheat and barley techniques. The

systematic objective labeling logic

developed for corn and soybeans was

modified for wheat and barley and the

increased use of spectral aids was incorporated into the logic. The techniques developed during the transition

year for wheat and barley were also incorporated into this new labeling logic

approach. The "new" wheat and

barley logic and procedure were

tested twice during the fiscal year. The

first was a six-segment "shakedown"

test to identify procedural and logic

problems; the test results were encouraging and only minor modifications were made. Using the new procedure, called the "reformatted"

wheat and barley procedure, the US.

wheat and barley exploratory test was

then conducted using 11 segments.

The results indicated some previously

undetected problems with the procedure and modifications are currently

being made before its use in the fiscal

year 1981 U.S. Wheat and Barley Pilot

Test. Simultaneously with the U.S.

wheat and barley exploratory test, an

evaluation of a second wheat and

barley procedure, the "integrated"

procedure, was conducted; this less

systematic more labor-intensive procedure was also evaluated.

The corn and soybeans efforts of

ERIM and UCB have involved modifying the JSC-developed corn and soybeans decision logic procedure

developed in fiscal year 1979 and incorporating the use of spectral and

spatial transformations developed by

the supporting research and technology community. These developmental efforts have been continuously

reviewed by JSC, and JSC has conducted a preliminary review of the

corn and soybeans labeling logic. The

first end-to-end test of the procedure

and logic developed by ERIM and UCB

is planned for early in fiscal year 1981

as part of the 1981 U.S. Corn and Soybeans Pilot Experiment.

In the area of sampling and aggregation, a new weighted aggregation approach has been developed

and tested that establishes a more

valid technique for handling the "nonresponse" areas, or areas not adequately represented because of poor

satellite acquisition histories. Poor

satellite acquisition can result from

cloud cover, operational constraints, or

equipment malfunctions. Simulated

aggregation software was developed

to permit simulating the performance

in area and production estimation over

a region, assuming different values for

within-stratum variance and for nonresponse. Sample frame development

for foreign areas to be addressed in

later AgRISTARS experiments is

progressing well. Indicator regions

have been selected in Brazil, Argentina, the U.S.S.R, and Australia and

sample segments have been selected

to support the exploratory experiments

in these countries.

67
Wildland Vegetation Resource

Inventory

The joint NASA and Bureau of Land

Management (BLM) Application Pilot

Test was accomplished through an offsite contract (ESL Incorporated of Sunnyvale, California) to NASA to test and

implement an interactive Wildland

Vegetation Resource Inventory System

based on remotely sensed data and

oriented to the BLM state and district

office management requirements. The

project was planned in three phases

with test sites in Alaska, Arizona, and

Idaho.

The Alaska phase, May 1977 through

July 1978, mapped vegetation types

and developed accuracy relationships

using various scales of aerial photography and ground data applied to

Landsat digitally processed data.

Landsat spectral classes were

developed with a maximum likelihood

classifier; these classes were then described through photointerpretation of

large-scale (t :1 200) color aerial

photography coupled with selected

plots of ground-truth data to correlate

the photointerpretation with ground

conditions. An example of a classification of the Alaska Test Site is shown in

figure 1. BLM resource personnel were

trained in the theory and application of

resource measurement and estimation

procedures and how, when, and where

remote-sensing techniques should be

applied to provide cost-effective

resource inventories and assessments.

The second phase, September

1978 through June 1980, modified the

system developed during the Alaska

phase and tested it in the desert

ecosystem of Northwestern Arizona.

Figure 1 ._Landsat vegetation classification of the Alaska Test Site.

:;:: ,

_,_.._L_ \k

m ....

m ........... . _ ._

68

Q mmm,m_
This phase went one step further by

demonstrating a multi-resource inventory with productivity estimates for

range forage, timber production and

woodland volume (fig. 2 and table 9.

"[raining of BLM resource personnel

continued. Concurrent with the contractor Phase II activities, BLM tested

its in-house expertise, with assistance

from the Earth Resources Observation

Satellite (EROS) Data Center, by accomplishing a Landsat vegetation

resource inventory over the same test

site in Arizona.

The final phase of the NASA support began in December 1979 and involves project documentation, implementation and documentation of software, and support for a final project

conference in early 1981. The Application Pilot Test is scheduled for

completion in March 1981.

BLM purchased a minicomputer

system in the fall of 1979 and established a Remote-Sensing Branch at

the Denver Service Center for operational support of ongoing projects.

BLM is presently using these

capabilities during the final project

test phase at the Idaho Test Site. The

results of this remote-sensing effort, to

be completed in late 1980, will provide inputs for preparation of an environmental statement.

"[he overall success of the Application

Pilot Test is evidenced by the remotesensing processing and analysis

capabilities established at the Denver

Service Center and the inclusion of

remote-sensing requirements in the

BLM budget submission.

Figure 2.--I_andsat vegetation classification of the Arizona Test Site.

eARE| LAmD

i ws?fm

LANDSAT

_,,. VEGETATION

*- CLASSIFICATION

ARIZONA STRIP DISTRICT, ARIZONA

LEVEL 111 CLASSIFICATION

MAPPING UNIT: IOACRF, S

t4 HECTARES}

SOURCE DATA: AUGUST 26, 1977

SCENE I.IX.2947.17074

|ItlIAHVllIIA]Ill N{{{li(! *|VIIT|I_ {TSTIM

IASA/|LM APPLICATI0m Pttet rtS_ PNJ$[ II

AIAtTSlW |V ISL IKOP0|_TCe

TABLE I._ JUNIPER CUBIC VOLUME ESTIMATES a FOR SELECTED ARIZONA TEST SITE ALLOTMENTS

ALLOTMENT TOTALAREA, TOTAL VOLUME, STANDARD RELATIVE AVERAGESIZE,

ACRES VOLUME, FT3/ACRE ERROR STANDARD FT

FT3x 10_ ERROR

Wolfhole 13308 2215 178.4 45.9 0.26 t 4.0

b(1479, 2951) b(119.1, 237.7) b(8.9, 19.1)

Wolfhole 14727 2770 188.2 53.5 .28 15.6

Mountain (1756, 3785) (119.3, 257.1) (9.8, 21.5)

Blackrock 37323 4831 147,2 40.6 .28 12.4

(3119, 6543) (95.1, 1994) (6.6, 18.2)

Total 65358 9817 163.7 16.7 ,10 13.6

(8533, 11101) (142.3, 185.2) (7.8, 19.4)

aEstkmales apply 1o BLM rand only

bNumbers in parentheses are 80-percent confidence bn[er,,'als

69
Texas Natural Resources

Inventory and Monitoring System

The purpose of this project is to

develop, test, and evaluate approaches and procedures for integrating Landsat and other remote-sensing

data with more conventional data

sources (e.g., census, maps, and field

surveys) to augment and make more

effective the existing information data

base supporting Texas natural

resources management agencies. The

major goal is to integrate the use of

Landsat and other remote-sensing

data into the day-to-day decisionmaking processes of the Texas resources

management agencies. To accomplish this goal, the utility and costeffectiveness of the information

derived from remotely sensed data

must be evaluated in an operational

environment using ongoing management requirements of selected state

agencies as evaluation criteria.

This project is a joint effort of the JSC

Earth Observations Division and a consortium of 13 Texas agencies known

as the Texas Natural Resources Information System. The project started in

June 1978 and is expected to span 3

years. The project will develop, test,

and evaluate a Texas Natural

Resources Inventory and Monitoring

System based in part on information

derived from remote sensing. The

system will consist of three components: a remote-sensing information

subsystem, a geographic information

subsystem, and a natural resources

analysis subsystem. Figure 1 illustrates the type of output products that

will be produced.

The major responsibility of NASA is

to assist Texas in upgrading its existing experimental remote-sensing data

analysis capability and to interface

this capability with other sources of

natural resources information available

to the state. The software capability is

being developed in two parts. The first

part was completed by NASA in early

fiscal year 1980. The major responsibility of Texas includes developing

the remaining remote-sensing software; expansion of the existing

geographic information subsystem;

development of the natural-resources

analysis subsystem; and preparation,

testing, and evaluation of output products.

Figure 1.---Computer classification.

] F -bTo] ,q,2 ],3I" 1,51'61E 

7O

WATER

Clear water

Slightly turbid water

Moderately turbid water

UNCULTIVATED LAND

Woodlan(l

Brushland I

Bru'_hland II

Range, land I

Rangeland II

BARREN/WETLAND

H

HI

IV

v

OTHER

Vegetated clayey substrate

Suburban lawns and streets

Barren/welland IV V boundaries

Industrial complex and unclassified

To carry out the responsibilities of

both parties, a Memorandum of Understanding was instituted. Responsibility

for management of the project is

shared by a Texas Project Manager

and a JSC Deputy Project Manager.

The technology developed for this

project will be documented for transfer

to the public domain through NASA's

Regional Technology Transfer Centers

and the Computer Software Management and Information Center (COSMIC). Texas will also furnish a final report on the utility of the system and a

cost and accuracy analysis study.

Accomplishments during the past year

are as follows.

t. Development of remote-sensing

data analysis software and procedures

to support use of the color graphics

terminal for the display and enhancement of Landsat multispectral-scanner

(MSS) digital data. The system is

capable of displaying raw or classified

Landsat 1,2, and 3 MSS digital data as

well as performing limited data enhancements including contrast stretching,

band ratioing, and edge sharpening.

2. Applications were identified by

state agencies for the five test sites in

the areas of coastal zone management, forestry, water resources,

mineral resources, and wildlife management. Remote-sensing data were

collected at four test sites. This broadbased application testing will help

demonstrate the statewide applicability of remote-sensing technology.

3. Development of the geographic

information subsystem and the natural

resources analysis subsystem was initiated. These subsystems will provide

the means for integrating and analyzing the information to support the

specific state agency applications.
Orbiter Camera Payload System

The Orbiter Camera Payload System

was a fiscal year 1978 new start and is

funded through fiscal year 1984. This

camera system is composed of a

large-format camera, an electronics

control assembly, a high-pressure gas

supply system, and a flight support

structure. The system is designed for

operation in the Orbiter cargo bay (fig.

1) to obtain high-resolution vertical

stereoscopic photographs of the

Earth's crustal and surface features

from orbital altitudes. The large-format

camera (fig. 2) produces photographs

of high geometric fidelity for cartographic applications where precise

height and position of surface points

are required. In addition to the cartographic applications, the stereoscopic photographs will be of particular value to the geological explorer

(fossil fuels and minerals), the

engineering geologist, and other investigators of renewable and nonrenewable resources.

During fiscal year 1980, all development and manufacturing tasks were

completed and all phases of testing

were nearly completed. Factory testing and calibration of the cartographic

lens assembly (fig. 3) was completed.

The final two quarters of fiscal year

1980 have been devoted to subsystems verification and full system

environmental and functional testing.

A thermal-vacuum retest has been

scheduled for the first month of fiscal

year 1981, and delivery of the fully

operational flight system and groundsupport equipment is scheduled for

November 1980.

Figure 1 ..--Orbiter cargo bay.

A tentative mission assignment for the

Orbiter Camera Payload System has

been made using the space available

on Space Transportation System (STS)

mission 26. This mission is planned for

a launch to a 280 inclination in September 1984. For this mission, the

camera system will be configured as

part of the proposed Office of Space

and Terrestrial Applications (OSTA-3)

payload. This mission will be conducted as an engineering evaluation

flight of the Orbiter Camera Payload

System and will derive mission planning and postmission data analysis

support from the Large Format Camera

Interagency Working Group.

Figure 2.--Large format camera (LFC). Figure 3.--Cartographic lens assembly.

L i

71
Extended Scene Radar

Calibration

The extended scene radar calibration

effort was initiated to verify the precision and accuracy of scatterometers

and imaging radars used for remotesensing investigations on JSC aircraft.

The precision and accuracy of

microwave sensors must be verified to

ensure that day-to-day variations in

their data sets are truly remotely

sensed phenomena rather than sensor

variations.

The experiment approach was to

carefully measure the radar reflectivity

of large homogenous test areas (extended scene) with a highly calibrated

ground scatterometer system. These

test areas were then overflown by the

aircraft sensors and the two data sets

analyzed with respect to precision and

accuracy to provide a measure of

calibration to the aircraft sensors for

extended scenes. Data sets are taken

at 1.6, 4.75, and 13.3 gigahertz.

The effort was initiated in 1977, with

test sequences performed in 1978 and

1979. In 1979, the effort was expanded to cover the effects of row

spacing on radar reflectivity or backscatter curves. In fiscal year 1980, a

test series was again performed at

Northrup Strip, White Sands Missile

Range, and Jornada Experimental

Range in New Mexico. The Northrup

Strip data will be used as baseline

data for radar calibration. The Jornada

data were gathered to study the

effects of row height on radar reflectivity. Figure 1 is a plot of the backscatter difference between cross-row

and along-row radar data of t.6

gigahertz for two different field conditions. The first data set was taken over

rows that were 25.4 centimeters high.

The second set was taken over rows

that were 15.0 centimeters high. Row

spacing was the same in both sets.

The peaking effect caused by the rows

is present in both but gets smaller with

reduced row height. Analysis of the

aircraft data also showed that the

peaking was not present in crosspolarized data. Figure 2 shows the

new configuration of the ground scatterometer system. During fiscal year

1980, a new tower/trailer combination

was integrated into the system, providing a greater degree of transportability.

Figure 1,--Comparisonof angularresponseof themodulation function,

25

2O

_o=

15

10

DATA SET 1 (NOV 16, 1979)

X--_--i( DATA SET 2 (DEC 11, 1979)

1.6 GHz VV

I I I I I

10 20 30 40 50

I

6O

ANGLE OF INCIDENCE, DEG

Figure 2.--Ground scatterometersystem.

72
SIR-A Antenna Integration to

OSTA- 1 Pallet

The Shuttle Imaging Radar (SIR) A--

developed to evaluate the potential of

spaceborne imaging radar as a tool for

geologic exploration and, in general,

for mineral exploration, petroleum exploration, and structural mapping--is

part of the Office of Space and Terrestrial Applications (OSTA) 1 payload

to be flown on the Space Shuttle (SS)

2 mission. The SIR-A antenna was

developed by the JSC to be used with

the SlR-A electronics developed by

the Jet Propulsion Laboratory.

The SIR-A antenna, manufactured by

Ball Aerospace Systems Division, consists of seven microstrip array panels

mounted on a triangular support structure. The antenna is attached to the

OSTA-1 pallet by an aluminum truss

structure (fig. 1). The nondeployable

9.44- by 2.1-meter antenna is

mounted in the payload bay in a fixed

position at 47 °. Thermal protection is

provided by the multilayer aluminized

mylar covering the support structure

and by the Beta cloth covering the

total system.

The 400-pound antenna system was

installed on the OSTA-1 pallet in the

Operations and Checkout Building at

the Kennedy Space Center in January

1980. Verification of proper fit was

made. However, the planned course

alinement was deferred because of an

out-of-plane condition of the pallet

caused by the pallet support method

used in the engineering model stand.

Course alinement is anticipated to be

completed when the OSTA-1 payload

is located in the cargo integration test

equipment stand. Electrical testing of

the antenna has been successfully

completed. These tests consisted of

(1) a continuity check of reflection and

loss through the antenna and (2) a

coupling check of antenna/electronics

and the interface by injecting a signal

into the antenna and monitoring the

radar system output.

Figure 1.---SIR-A antenna installed.

73

Office of

Space Sciences

Significant Tasks

77

78

80

81

Martian Weathering Simulation

Funded by: Planetary Geology (UPN-151)

Technical Monitor: R. V. Morris/SN7

Task Performed by: Lyndon B. Johnson Space Center

New Results from a Lunar Core

Funded by: Planetary Materials (UPN-152)

Technical Monitor: D. S. McKay/SN6

Task Performed by: Lyndon B. Johnson Space Center

Complexity of the Lunar Crust

Funded by: Planetary Materials (UPN-152)

Technical Monitor: P. Butler/SN2

Task Performed by: Northrop Services Inc.

Contract NAS 9-15425

Meteorite Types in the Antarctic Meteorite Collections

Funded by: Planetary Materials (UPN-152)

Technical Monitor: D. D. Bogard/SN7

Task Performed by: Northrop Services Inc.

Contract NAS 9-15425

82 Young Meteorites From an Earthlike Parent

Funded by: Planetary Materials (UPN-152)

Technical Monitor: Laurence E. Nyquist/SN7

Task Performed by: Lyndon B. Johnson Space Center

84 Moon Rock Curation

Funded by: Planetary Materials (UPN-152)

Technical Monitor: P. Butler/SN2

Task Performed by: Northrop Services Inc.

Contract NAS 9-15425

85 Origin of the Earth's Continental Crust

Funded by: Planetary Geochemistry and Geophysics (UPN-153)

Technical Monitor: Jeffrey Warner/SN

Task Performed by: Lyndon B, Johnson Space Center

86 Role of Anorthositic Rocks in Early Evolution of Planetary

Crusts

Funded by: Planetary Geochemistry and Geophysics (UPN-153)

Technical Monitor: W, C. Phinney/SN6

Task Performed by: Lyndon B. Johnson Space Center

75
87

88

89

90

91

92

The Dynamic Crystallization of Basalt

Funded by: Planetary Geochemistry and Geophysics (UPN-153)

Technical Monitor: G. Lofgren/SN6

Task Performed by: Lyndon B. Johnson Space Center

Antarctic Dry Valleys: Terrestrial Analog of the Martian

Surface

Funded by: Mars Data Analysis Program (UPN-155)

Technical Monitor: E K. Gibson/SN7

Task Performed by: Lyndon B. Johnson Space Center

The Chemistry of Micrometeoroids

Funded by: Spacelab Payloads (UPN-834)

Technical Monitor: F. Horz/SN6

Task Performed by: Lyndon B. Johnson Space Center

Remote Sensing of Lunar Rock Composition by Thermal

Infrared Measurement

Funded by: Planetary Astronomy (UPN-196)

Technical Monitor: A. E. Potter, Jr./SN3

Task Performed by: Lyndon B. Johnson Space Center

Advanced Hyperthermia System

Funded by: Life Sciences (UPN-199)

Technical Monitor: SD and ED

Task Performed by: Memorandum of Understanding

Lyndon B. Johnson Space Center

Stehlin Foundation for Cancer Research

Linear Accelerator for Human Vestibular Research

Funded by: Life Sciences (UPN-199)

Technical Monitor: M F. Reschke/SD

Task Performed by: University of Michigan

Contract NAS 9-15663

93 Nuclear Cardiology Imaging System

Funded by: Life Sciences (UPN-199)

Technical Monitor: D, L, Teegarden/SN

Task Performed by: Lockheed Engineering and Management

Services Co., Contract NAS 9-15800

94 Mobile Biological Isolation System

Funded by: Life Sciences (UPN-199)

Technical Monitor: A, Mandel/SD

Task Performed by: ILC Dover

Contract NAS 9-15946

76
Martian Weathering Simulation

Weathering is a surface process that is

universal to all planetary bodies. The

difference among planetary bodies is

in the form weathering takes in

response to its energy source. For

planetary bodies having atmospheres,

such as the Earth, the energy source is

the secondary dissipation of

electromagnetic radiation that arrives

at the surface and heats the atmosphere. For planetary bodies having virtually no atmosphere, such as

the Moon, the energy source is the

direct transmission of energy in the

form of meteorites, radiation, and

atomic and nuclear particles impinging on the surface. For planetary

bodies having thin atmospheres, such

as Mars, the energy source embodies

aspects of both of the above limiting

cases.

Data on planetary surface materials

obtained remotely (such as from

Earth-based telescopes or spacecraft

imagery), in situ (such as by the Viking

landers), or directly (such as by

analyses of returned surface samples)

have been influenced by weathering

processes. Only when the extent and

nature of weathering processes (and

of other surface processes such as

erosion, transportation, and lithification) are sufficiently understood can

the data on surface materials be properly interpreted and used to construct

models about the constitution and

evolution of a planetary body. The accuracy and predictive capability of the

models are directly related to how well

the changes introduced by weathering

are recognized and understood.

At the present stage of the scientific study of Mars, it is of primary importance to establish to what extent

the remote sensing and Viking lander

data on surface material reflect primary versus secondary (weathered) surface material. One important avenue

to use in determining and evaluating

the nature and influence of weathering

on Mars is through laboratory simulation experiments. In such experiments,

terrestrial materials, including both

primary and secondary rock types and

synthetic materials, are weathered in a

simulated Martian environment.

Figure 1.---Martian Weathering Simulation Facility.

_JP

A Martian Weathering Simulation

Facility (MWSF) is operational at the

Johnson Space Center (fig. 1). The

apparatus in this facility can simulate

superficial conditions on Mars in terms

of temperature (below -10 ° C), atmospheric pressure and composition

(mainly carbon dioxide at -- 6 tort),

electromagnetic radiation environment (ultraviolet through infrared), and

the normal Martian variations in these

parameters. One of the studies performed in this facility is that of the

kinetics of magnetite oxidation in the

presence of ultraviolet radiation. Previously, researchers thought that magnetite would efficiently oxidize to ferric

oxide phases under Martian conditions

of ultraviolet radiation. This process

was thought to be the dominant one

that has resulted in the apparently

high-oxidation state of the Martian surface. However, experiments performed in the Martian Weathering

Simulation Facility revealed that this

process does not proceed at a perceptible rate. What appears to happen is

that Martian surface materials are

heated by the infrared in sunlight and

the oxidation proceeds rapidly under

the effect of this heating.

77
New Results from a Lunar Core

An Apollo 15 lunar core recently

analyzed in detail has revealed some

interesting results. This core

(15010/15011 ) is a double-drive tube

that was taken by Astronauts Dave

Scott and Jim Irwin at Station 9A about

20 meters from the rim of Hadley Rille

(fig. 1). The 55-centimeter-long core

was carefully dissected, described,

and photographed at JSC, a process

which took nearly 2 years. Samples

from the core were then analyzed by

principal investigators at JSC and

elsewhere by a variety of techniques

and instruments.

The dissection revealed nine separate

stratigraphic units which differed

slightly in color or texture. The core

contained a number of small rocks,

especially toward the bottom of the

core (fig. 2).

This core has several interesting

features related to its sampling location near the edge of the rille. Most of

the rock, mineral, and glass fragments

are derived from basalt, reaffirming the

interpretation that basalt flows underlie much of the site and comprise the

edges of the rille. The largest rock

fragment shown in figure 2, for example, is a basalt fragment. However,

fragments of highland rocks are present throughout the core and are

surprisingly slightly more abundant

toward the bottom. Figure 2 also

shows a whitish fragment which is

probably an anorthositic breccia. Such

fragments are probably derived from

the Appenine Front some 4 kilometers

away from the core site.

The soil in the core is relatively

coarse-grained with a mean grain size

of about 95 micrometers; it is slightly

coarser toward the bottom. The ferromagnetic resonance profile for the

core reveals that whereas the core is

slightly more mature in its upper half

Figure 2.---Photograph of the bottom of

partly dissected core 15010/15011. Three

rock fragments are visible. The lowermost is

apparently an anorthositic breccia; the

other two are basalts.

Figure 1.--Map of the Apollo 15 site showing the location of the four cores. When

completed, analyses of these cores will

provide three-dimensional control for the

Apollo 15 re _olith.

_R_ APOLLO 15 CORES

STA _15010115011

.,o,

/ST OEOROE\ "_--',_.-"O_.l

km CRATER STA 6

78
(fig. 3), it does not have the weltdeveloped maturity profile commonly

found in other lunar cores. This limits

the time the core material was in place

to 100 million years or less. Furthermore, rare-gas data reveal that the

core does not have a significant production profile of cosmogenic species

such as 3helium, 21neon, 3aarg on,

8Okrypton, and _26xenon. This means

that the core material was not irradiated by cosmic rays for very long, certainly no longer than 1O0 million years.

Yet individual samples from the core

were exposed to cosmic rays for 300

million years or more. This indicates

that most of the core material was

preirradiated somewhere near the

lunar surface before the material was

incorporated into the stratigraphic section sampled by the core. The formation of the present stratigraphic sequence occurred less than 1O0 million

years ago, which is a short time compared to the age of the basaltic

bedrock (approximately 3.3 billion

years). The lack of a well-developed

soil profile shown by the ferromagnetic

resonance data (fig. 3) is also supported by grain-size data, solar wind

gas data, and agglutinate abundances.

The unusual features of this core include the relatively immature state of

the entire core, the lack of welldeveloped maturity profiles, the

relatively homogeneous characteristics of the core throughout its

length, and the relatively short period

of time that the core material resided

in its present position as sampled by

the astronauts. These features require

an unusual set of circumstances, and

the explanation is probably closely

tied to the unusual location of this

core. The steep Hadley Rille has apparently acted as a sink for regolith

that has been stirred and ejected by

meteorite impact, preventing the

regolith from becoming very thick near

the edge of the rille. The regolith at the

core site is estimated to be only about

1-meter thick compared to a more norFigure 3..--Ferromagnetic resonance (FMR)

profile of soil maturity throughout the length

of core 15010/15011.No part of the core

contains mature soils commonly found in

other cores.

FMR MATURITY'--["

0 20 40 60 80 100

I I, I 0

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,' %

:," I0

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mal thickness of about 5 meters on the

fiat terrain near the Lunar Module. The

thinness of the regolith near the edge

of the rille causes a relatively rapid

turnover, prevents maturity profiles

from developing, and prevents the

development of very mature soils

because they are rapidly diluted or

covered by fresh ejecta. The sampling

location, therefore, is the cause of the

core's rather unique properties and it

provides new insight into lunar regolith

processes. This core may also be the

best prototype for some types of

asteroidal regoliths characterized by

extreme thinness and may help to explain the lack of mature soil features in

most regolith-derived meteorites. Core

15010/1501 1 is consequently an extremely important part of the Apollo

sample collection.

79
Complexity of the Lunar Crust

Much of the Moon's evolution has involved igneous processes; i.e., those

in which silicate liquids (magmas) are

produced by the melting of the Moon.

These liquids can crystallize to their

own compositions as many lavas do on

Earth; or the crystals that form can subsequently accumulate and form rocks,

at the same time changing the composition of the liquid. Different crystal

types affect the liquid in different

ways, influencing the minerals that

later crystallize from the liquid. For instance, the mineral olivine, which is

magnesian, depletes the liquid in

magnesium and subsequent minerals

are less rich in magnesium than they

would otherwise have been. Even

though the olivine may no longer be

seen, its effects can be inferred by inspecting the rocks that accumulate

from the later minerals. Magnesium is

a major element and olivine is a major

phase, but the same kinds of effects

can be seen for trace elements and

trace minerals. The ratios of

titanium/samarium and scandium/

samarium have been used as tracers

of the history of lunar-highlands igneous rocks. Samarium is not easily

absorbed into any major minerals;

hence, as crystallization proceeds, its

abundance in the liquid increases. If

ilmenite crystallizes, then the titanium

in the liquid decreases and rocks

accumulating later have low

titanium/samarium ratios. Scandium/samarium is a similar indicator of

pyroxene crystallization.

The Moon does not have the same

composition throughout its depth; instead, like other planets, it has a crust

different from the interior. It was

realized early in lunar sample analysis

that the Moon has a plagioclase-rich

crust (an unexpected result) and that

this crust had formed not long after the

formation of the Moon itself.

Plagioclase is a light mineral and the

general interpretation is that the concentration of plagioclase in the outer

regions of the Moon was a result of its

crystallization and flotation from a

massive "ocean" of molten silicate.

We now know that there are many igneous rock types in the lunar highlands other than the very plagioclaserich ones, and the compositions of the

breccias (the impact-produced broken

and melted rocks that dominate the

highlands) suggest that they are a very

substantial part of the crust. These

rocks are more magnesian than are

the plagioclase-rich ones (anorthosites) and hence are known as the

"magnesium-suite" rocks. To understand the crust and its evolution, it is

necessary to understand the relationships between all the rocks. The

titanium/samarium ratios of the rocks

(fig. 1) show that the anorthosites

crystallized from a liquid from which ilmenite had not crystallized. However,

the magnesium-suite rocks crystallized from liquids from which ilmenite had at some time been

removed. This makes the origin of the

magnesium-suite rocks complex

because ilmenite is a mineral that

crystallizes only at an advanced stage

of the crystallization of a silicate liquid;

yet all the other characteristics of the

magnesium-suite rocks suggest that

they crystallized at an early stage of

crystallization (including the fact that

they are rich in magnesium) and certainly earlier than the anorthosites.

The conclusion is that the magnesium-suite rocks and the

anorthosites are not very closely related, but that the magnesium-suite

rocks are related to each other

because they have the same peculiar

characteristic of low titanium/

samarium, unlike terrestrial,

meteoritic, or other lunar rocks. The

scandium/samarium ratios show a

similarly perplexing depletion of

pyroxene in the magnesium-suite

parent liquid.

Because the magnesium-suite rocks

are too dense to have floated over a

silicate liquid, the formation of the

lunar crust must have involved a more

complex origin than simply the flotation of rocks over a magma "ocean"

(although this probably did happen to

produce the anorthosites). There are

several possibilities, but none yet

seem to be quite right. Further work

with trace elements will probably

solve the problem rather than just

demonstrate its existence.

Figure 1 .--The titanium/samarium ratios of Moon rocks.

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8O
Meteorite Types in the Antarctic

Meteorite Collections

During the past year, meteorites with

masses greater than 150 grams collected by the joint Japanese-American Antarctic expeditions for the field

seasons of 1977-78 and 1978-79 have

been classified at the JSC and at the

Smithsonian Institution. Traditionally,

meteorites have been classified in the

broadest sense by the amounts of

metal and silicate they contain. Thus,

irons are composed chiefly of metallic

nickel-iron but may contain silicate inclusions. Stones are composed mainly

of silicates but may contain more than

24 percent nickel-iron. The stones can

be divided into two groups based on

their textures: chondrites and

achondrites. Chondrites contain

chondrules, which are spherical to

subspherical bodies composed mainly

of silicates, and range in size from less

than 0.1 millimeter to more than 0.5

centimeter. Chondrites are classified

by their chemistries and mineralogies.

The amphoterites (LL group) are

regarded as a subgroup of the olivinehypersthene chondrites (L group) by

some researchers, but others regard

them as a separate type of ordinary

chondrite with equal stature to the

olivine-bronzite chondrites (H group)

and the olivine-hypersthene

chondrites (L group). The carbonaceous chondrites are generally

characterized by a high content of

volatile elements and compounds that

include water, sulfur, and rare gases.

The most widely accepted classification of petrologic types of chondrites is

based on their chemistries,

mineralogies, and textures. This model

was proposed in 1967 by VanSchmus

and Wood and assumes a progressive

thermal metamorphism (type 6 being

the most highly metamorphosed) to

account for the textural and chemical

variations.

Stony meteorites without

chondrules are termed achondrites.

The achondrites are generally divided

into two groups based on calcium content. Calcium-poor achondrites include the aubrites, diogenites,

chassignites, and ureilites. The

calcium-rich achondrites include

eucrites, howardites, angrites, and

nakhlites. The shergottites are considered to be eucrites by some

researchers but the majority believe

that they are sufficiently distinct to retain the term shergottite.

The complete classified collection of

the 1977-78 season consists of 103

meteorites including 7 irons, 2 carbonaceous chondrites, 5 achondrites,

49 H-group chondrites, and 39 L- or

LL-group chondrites. Achondrites

represent five individual classifications: mesosiderite, ureilite, diogenite,

eucrite, and winonaite. One petrologic

type 2 and one petrologic type 3 carbonaceous chondrites are present.

The 1978-79 collection of 69 specimens has been classified and includes 31 L- or LL-group chondrites,

19 H-group chondrites, 10 irons, 8

achondrites, and 1 carbonaceous

chondrite. Achondrites are represented by 5 polymict eucrites, 1

aubrite, and 2 ureilites. The carbonaceous chondrite is petrologic

type 2. The histogram (fig. 1) shows

the distribution of the ordinary

chondrites in the 1977-78 collections

by chemical group and petrologic

type.

The distribution of chemical groups

within each petrologic type of ordinary

chondrites is similar for both collections. The petrologic type 6 specimens

are dominated by the L-group

chondrites, and the petrologic types 4

and 5 meteorites are overwhelmingly

represented by the H-group

chondrites. Because of the distinct

groupings and similarities between intraspecimen and interspecimen comparisons, it is believed that the samples represent a limited number of

falls.

Figure 1.--Distribution of Antarctic meteorite collections.

2,2

28

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24

20 L

12

8

4

0

6

r-] 1977

• 1978 H

H

5 4 3

PETROLOGIC TYPE

The 1979-80 collection is comprised

of 83 meteorites including 1 iron, 75

chondrites, and 7 achondrites. The

chondrites are estimated to range in

mass from tess than 20 grams to more

than 3 kilograms. The iron has a mass

of approximately 10 kilograms and is

known to have silicate inclusions that

are believed to be of orthopyroxene

composition. Of the seven achondrites, one is classified as a eucrite,

one as a howardite, and three as either

polymict eucrites or howardites. Their

masses range from 86.4 grams to 7.1

kilograms. One achondrite (2.8

kilograms) is classified as an

anomalous diogenite based on its

petrographic characteristics. The last

achondrite (7.9 kilograms) is

classified as a shergottite and is one of

the four known shergottites in the

world. It will certainly be of great interest to the scientific community

because much speculation about its

origin still remains.

81
Young Meteorites from an

Earthlike Parent

Meteorites have long been objects of

curiosity. Centuries ago, stones that

fell from the sky created sufficient interest among observers to ensure their

preservation as evidence of a poorly

understood natural phenomenon. Only

relatively recently have scientists

possessed the analytical tools with

which to understand the origins of

these visitors from space. As a result of

intensive laboratory studies, it has

been shown that most meteorites are

both ancient and primitive. Chemical

analysis reveals that the majority of

stony meteorites are undifferentiated;

i.e., the relative abundances of nonvolatile elements in these meteorites

are close to the relative abundances of

the same elements in the Sun. Such

meteorites are said to be primitive.

Radiometric dating of primitive undifferentiated meteorites shows that

they are nearly 4.6 billion years old.

Most other meteorites and some lunar

rocks also are about 4.6 billion years

old. Although no terrestrial rock is this

old, "model ages" can be calculated

for the bulk Earth; such ages are also

about 4.6 billion years old. Thus, 4.6

billion years is believed to be the age

of the solar system.

Meteorites tell us more about the

solar system than just its age,

however. Each meteorite type was

formed by a specific set of processes.

Some of the most interesting

meteorites are the basaltic

achondrites. They are called basaltic

because they are texturally and

chemically similar to terrestrial

basalts, which are solidified melts

from the interior of the Earth.

Spacecraft exploration has shown that

basalts occur on the surface of the

Moon and on the other terrestrial

planets as well as on Earth. Because

basalts are melt products from the interiors of planets, their chemical compositions vary with the variations in the

bulk composition of their parent

planets. The ages of basalts are also

controlled by the properties of their

parent planets. Thus, large planets

that contain large quantities of heatproducing elements and that cool

slowly have produced basalts over

most of the solar system history. Earth,

Mars, and Venus are examples of such

planets. Smaller planetary bodies

82

have cooled enough so that basaltic

volcanism has ceased. The Moon is an

example of such an object; basaltic

volcanism on the Moon ceased about

3 billion years ago. Most basaltic

achondrites have ages of about 4.6

billion years, showing that their

parents were hot near the beginning of

the solar system but cooled very

rapidly. The early heat source remains

a matter of some speculation;

however, rapid cooling is consistent

with the widely accepted concept that

the asteroid parents for these

meteorites are small planetary bodies.

Some basaltic achondrites, the

nakhlites and the shergottites, have

young radiometric ages. Identification

of their parent planets remains a tantalizing puzzle. Young basalt ages normally imply a large planet. But which

planet, and how were rocks hurled

from its surface into space so that they

might later fall on Earth? The natural

transport of rocks from the surface of

one large planet to the surface of

another seems so improbable that

most scientists have sought other explanations. A favorite alternative hypothesis is that the meteorites were

really formed about 4.6 billion years

ago, like other achondrites, and have

simply had their radiometric clocks

reset by the heat accompanying

asteroid or meteoroid collisions in

space.

Work directed towards solving the

nakhlite/shergottite puzzle is currently

underway at the JSC and elsewhere.

The emphasis has been on the

shergottites, only two of which were

known to exist at the beginning of the

study. One, called Shergotty, fell in India in 1865; another, called Zagami,

fell in Nigeria in 1962. A third shergotrite-like meteorite was found in the

Antarctic in 1977; it is called Allan

Hills 77005. A fourth shergottite-like

meteorite has recently been identified

among meteorites found in the Antarctic in 1979; it is called Elephant

Moraine A79001. Radiometric dating

of the first three meteorites has

repeatedly yielded young ages. Figure

1 shows results obtained by the

rubidium-strontium method. In the

representation of figure 1, the rock

ages are proportional to the slopes of

Figure 1 .---Geochronological results obtained by the rubidium-strontium method.

.73

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T = 164£ 12 m.y.

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I 0.721:.39 +_ 5

ALLAN HILLS 77005

T ]83__ 12 m.y.

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TBABI : 4.8AE

.70,

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87Rh/86Sr

1.5
the lines and correspond to the data

received when each meteorite was

measured for the various minerals. The

rubidium-strontium ages (T) of all

three meteorites are identical within

analytical uncertainty. An average age

is 177 million years. The slope of the

line labeled TBABI = 4.8 AE is close to

that expected for a "normal" meteorite

with an age of -- 4.6 billion years (1

AE = 1 billion years).

Ages obtained for the shergottites

by the 4°argon/39argon and samariumneodymium method (two other

radiometric techniques) are older than

the rubidium-strontium ages. These

results, in addition to petrographic evidence of shock metamorphism of the

mineral phases, strongly suggest that

the rubidium-strontium age has been

reset by a major collision. This conclusion does not solve the shergottite

puzzle, however. The samariumneodymium model ages of the

shergottites range from 2.8 to 3.6

billion years. These model ages give

an upper limit to the time since the

concentration ratio of two rare earth

elements, samarium and neodymium,

was last significantly changed.

Because the chemical behaviors of

samarium and neodymium are very

similar, it is extremely difficult to

change the samarium/neodymium

ratio of rocks except by special igneous processes. Thus, if the shergottires were really 4.6 billion years old,

they should have 4.6 billion years

samarium-neodymium model ages.

Thus, whereas the rubidium-strontium

ages clearly suggest a "metamorphic"

resetting, the samarium-neodymium

model ages also clearly suggest a

"young" igneous event. Exactly when

the igneous event occurred is not presently known with certainty. A lower

limit of 6 X 108 years ago is obtained

from samarium-neodymium analyses

of minerals from the Shergotty

meteorite. Geochemical considerations suggest that the "whole rock"

samarium-neodymium age of the

three analyzed shergottites, about

1.35 billion years, is both an upper

limit and a good approximation of the

shergottite age. This interpretation will

be strengthened if analyses of the

newly recovered shergottite also yield

the same whole rock age. Perhaps

coincidentally, the nakhlites also have

been dated as being 1.3 billion years

old. In the case of the nakhlites, the

same age has been obtained by the

rubidium-strontium, samariumneodymium, and 4°argon/39argon techniques. The nakhlite age must be considered as representing an igneous

event.

The most direct interpretation of the

radiometric age data for the nakhlites

and shergottites is that igneous melts

were formed on a planetary body

about 1 billion years ago. The only

known objects that produced melts of

about the right age and composition

are Earth and Mars. The volcanism

presently observed on the Jovian

satellite Io is too sulfur-rich to be

linked to the achondrites. Although the

nakhlites and shergottites have

chemical affinities to terrestrial

basalts, they cannot be terrestrial

rocks because they have been exposed in space for about 2 million

years as shown by the presence of

nuclear reaction products formed by

exposure to cosmic rays. Indeed, the

"cosmic-ray exposure" ages of the

meteorites are typical for stone

meteorites, suggesting origin in the

region of the asteroid belt, i.e., between Mars and Jupiter. The three

possible alternative origins are as

follows.

1. A giant "asteroid" was totally

disrupted less than 1 billion years ago.

2. The meteorites were somehow

blown off the Martian surface,

presumably by the impact of a giant

meteoroid on Mars.

3. The meteorites came from

Phobos or Deimos, the Martian

satellites.

Hypothesis 1 is ad hoc and not

easily tested. Hypothesis 3 is

dynamically more plausible than hypothesis 2; furthermore, the Viking

mission has shown that a significant

portion of Phobos has been blasted

away by a single meteorite impact. A

Phobos origin for the nakhlites and

shergottites would only push the problem back one step as Phobos is far too

small to have produced late-stage

melts. Perhaps tiny Phobos is a "late"

satellite of Mars, having been ejected

from and subsequently captured by

the parent planet. In this case, hypotheses 2 and 3 merge, suggesting

that Mars is the ultimate origin of

nakhlites and shergottites. This

possibility is now receiving serious

scientific consideration, particularly in

view of a remarkable chemical

similarity between the shergottites

and the Martian soil analyzed during

tile Viking missions.

83
Moon Rock Curation

The prime physical legacy of the

Apollo Program is the lunar sample

collection. That collection is not only a

symbol of a major national achievement but is also a scientific resource

that continues to be studied by scientists around the world. The 382

kilograms of lunar material is the

responsibility of the JSC Lunar Sample

Curator. Caring for the collection involves considerations for protection

from natural hazards such as hurricanes and tornadoes, theft, vandalism, and chemical contamination that

could produce subtle changes that

would invalidate time-consuming

scientific experiments.

Protection from natural hazards, theft,

and vandalism is offered by the 18-

inch reinforced concrete walls and the

15-ton vault doors of the Lunar Sample

Building completed in 1979. To protect the samples from the most significant natural threat to the Gulf Coast,

hurricane-induced storm tides and

flooding, all samples are stored in containers on a specially elevated second

floor of the building, 42 feet above sea

level. As an added precaution, when a

hurricane threatens the HoustonGalveston area, key records describing the processing and subdividing of

Figure 1.--Lunar samples are placed inside

a series of concentric barriers and containers.

 'CEL /

PURE NI[ROGEN

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the collection are moved into the

vaults on the second floor and the

vaults are sealed with special watertight covers. The ultimate precaution

to protect the Apollo treasure is the

storage of a representative 14 percent

of the collection in a vault at Brooks Air

Force Base in San Antonio, Texas, 320

kilometers west of JSC. Storing the

collection in two places assures that

scientific study can continue should

an unforeseen disaster strike either of

the two repositories.

To prevent pilfering and to keep

track of the geometric relations between individual sawed pieces of

rocks and of the depths of individual

strata in core samples, an elaborate

system of documentation is used.

Each step of the splitting up of a rock

or core is recorded photographically

and samples are repeatedly weighed

during processing. The magnitude of

this documentation has grown as the

collection has grown, from the 2169

samples actually brought back from

the Moon to over 66 000 current samples. Each sample must be continuously tracked and accounted for.

Using weight as a guide, 74 percent of

the collection has never left JSC

curatorial custody, 14 percent is stored

in San Antonio, 3 percent is currently

loaned to scientific investigators, 5

percent was loaned to investigators

and then returned to the curator, and 2

percent is on display in various

museums and traveling exhibits. Only

2 percent has actually been consumed

by scientific investigations.

Lunar samples typically contain

significant amounts of metallic iron,

virtually no water, and only a fraction of

a percent of alkali metals (such as

potassium and rubidium found in

natural terrestrial materials).

Therefore, the samples must be continuously protected from the Earth's atmosphere and dust. A series of concentric barriers and containers is

placed between the sample and the

environment (fig. 1). When stored,

each sample is enclosed in three

Teflon bags or in a combination of

three barriers made of Teflon bags and

metal containers. The bags are filled

with high-purity nitrogen gas and are

inside stainless steel glove boxes

filled with nitrogen that is continuously

measured for oxygen and water. The

cabinets are in a clean room supplied

with air from which all particles larger

than 0.0001 millimeter have been

filtered. Employees working in the

clean room wear special lint-free garments and enter through a succession

of progressively cleaner change rooms

(fig. 2).

As a further precaution against

chemical contamination, materials

touching the samples are carefully

controlled. Only objects made of

aluminum, stainless steel, or Teflon

are allowed to come in contact with

the samples, and the amount of other

materials inside the cabinets is held to

a minimum.

All the tools, bags, and metal containers that enter the glove boxes are

specially cleaned to remove all dust

and oily residues. The lunar samples

have tiny amounts of lead (tess than a

few parts per million) with an isotopic

composition that is critical in determining the age of many rocks. All the

chisels, tweezers, and other steel tools

used with the samples are specially

washed in diluted acid to remove any

adhering lead, in addition to the dust

and oily residues.

In the last 2 years, simplified versions

of the techniques used to curate the

lunar samples have been applied to

the meteorites collected from ice

fields in Antarctica.

Figure 2.---Employees working in the clean

room.

84
Origin of the Earth's Continental

Crust

The formation of a differentiated crust

appears to be a commonality in the

development of all rocky and icy

planets. This process is driven by the

tendency of each planet to rid itself of

excess internal energy. The origin and

development of the differentiated

crust on Earth, represented by the continents, is being investigated. The excess internal energy that drives the

formation and development of the

Earth's continents is the latent heat

released by the continuous crystallization of the inner solid-metal core from

the outer liquid-metal core.

The two extremes that may be considered as working hypotheses for the

Earth's continental crust are (1) the

mass of the continental crust separated from the mantle early in Earth's

history, and (2) the mass of the continental crust has been separating from

the mantle in a continuous manner all

through Earth's history. The truth must

lie between these two. The objective

of the ongoing research has been to

define the history of the separation of

mass from the mantle to form the continental crust. This task is complicated

because once a continental crust

forms, it is modified and remodified by

subsequent geologic events.

A well-known but surprising result

derived from a histogram of the ages of

continental rocks is that the ages form

several well-defined peaks (fig. 1).

This result has been interpreted as

evidence for the sporadic growth of

the continents; i.e., each peak in the

age histogram records an episode of

continental growth. The age

histogram, and thus the continental

growth record, has been traced back

to a major event between 2700 and

2500 million years ago. This event

marks the end of the period of Earth's

history known as the Archean.

The Archean is the time interval

from the oldest known rocks (3750

million years ago) to the major continent-making event between 2700 and

2500 million years. Examination of the

oldest rocks suggests that continental

material existed even earlier. The time

interval of continent formation that

predates the oldest rocks known is

called the Proto-Archean.

Evidence has been assembled that

indicates that the mass of continent

that separated from the mantle during

the Proto-Archean and the Archean is

approximately as great as the mass

that has separated since the Archean.

One important line of evidence is the

distribution of rocks that suggests the

measured ages do not record the time

a mass of continental rock was separated from the mantle but rather record

the latest modification of that mass of

continental rock. This is illustrated for

Archean rocks in the following argument.

Although typical Archean rocks yield

ages of 2700 to 2500 million years,

many rocks have been discovered during the past two decades that yield

ages as old as 3750 million years.

These older rocks have been discovered by the skill of geochronologists that enables them to "see

through" the 2700- to 2500-millionyear event to an earlier event in a

rock's history. There are two alternative models (fig. 2) to explain ages

greater than 3000 million years. In

model A, nuclei of continent material

existed at 3750 million years and the

common 2700- to 2500-million-year

ages represent later additions of continental material. In model B, most of

the 2700- to 2500-million-year-old

terrain existed at 3750 million years

and the younger age represents a time

when that terrain was thermally

modified. In a modeI-B world, a

geochronologist would be able to discover pre-3000-million-year-old rocks

in most places in the Archean that

were investigated in detail. In a

modeI-A world, geochronologists

would expect to discover pre-3000-

million-year-old rocks in only a few

places in the Archean terrain. The experience of geochronologists is that, in

most Archean regions studied in

detail, pre-3000-million-year-old ages

were discovered. This suggests that

model B is correct. Thus, the 2700- to

2500-million-year event is one of

modification of existing continental

material and not one of separation of

continental material from the mantle.

Figure 1 .---Distribution of ages in time of Earth's continental crust.

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AFTER GASTIL, 1960

500 1000 1500 2000 2500

AGE (MILLION YEARS)

3000

Figure 2.--Two alternative models displaying event sequence ages.

1

,;"L2k,P_

3 4 5

EVENT SEQUENCE

85
Role of Anorthositic Rocks in

Early Evolution of Planetary

Crusts

Significant contributions to the growth

of early planetary crusts are made by

extrusive and intrusive melts. These

melts generally are derived from mantle material and provide the major constraint for the thermal and chemical

history of the mantle during early

crustal evolution. Formation of melts

apparently occurs on all planets as indicated by samples from the Moon

and Earth and as interpreted from

remotely sensed data from Mars,

Venus, and Mercury. On Earth, the occurrence of early crustal rocks is

limited only to the Precambrian shield

areas of the continents. The earliest

preserved rocks derived from melts

are the Archean volcanic and associated anorthositic intrusive rocks that

formed primarily over the period between 3.7 and 2.7 billion years ago

reaching a peak at about 2.7 billion

years.

The work of the past year indicates

that anorthositic rocks are common

in Archean terrains although volumetrically minor. At least seven

anorthositic complexes occur in the

Superior Province of the Canadian

Shield and similar units occur in similar settings in Archean terrains of other

continents. Nearly all of the complexes

have an unusual and distinctive

feldspar texture in the anorthositic

rocks in which ptagioclase occurs as

roughly equidimensional grains ranging from pea to grapefruit size (fig. 1).

In some cases, various grain sizes are

mixed; in others, grain size is

homogeneous. This texture is distinctly different from that of younger

rocks in which plagioclase commonly

occurs in elongate laths and suggests

a significantly different history.

Studies have demonstrated an unusual

and consistent average composition

for several Archean anorthositic complexes (table 1) suggesting that they

formed from either an unusual source

material or as cumulate complements

of associated volcanic sequences that

are derived from more typical mantle

materials. If the former is true, then the

unusual source material may represent

heterogeneities in the mantle caused

by very early separation of the Earth's

crust and mantle. If so, a better understanding of the early evolution of

planetary crusts may be gained.

Figures 1 .---Large equidimensional crystals

in anorthositic rocks. (a) Golfball-size

crystals from the Bad Vermilion Lake intrusion. (b) Grapefruit-size crystals from a

thick sill in Manitoba. TABLE I.--AVERAGE COMPOSITIONS: ANORTHOSITIC

COMPLEXES

Fisken- Limpopo, Bad Vermilion Shawmere Sittampundi

aesset Messina Lake (OGS (OGS maps (Ramadurai

(Windley) (Barton maps and and map,

et al.) analyses) analyses) Subramaniam

analysis)

S_O 465 49.9 48 4 499 4452

TIP:, 4 3 4 2 .11

AbO, 23.2 24 3 235 241 25 77

FeO* 53 49 6 3 3 8 595

MnO 1 1 3 1 10

MgO 63 5 3 51 57 6 79

CaP 141 126 137 135 1454

Na:O 1 6 20 18 20 1.16

K_O 2 5 1 2 04

P_O_, 05 05 1 05

HI,O ± 9 59

MgO/ 68 66 58 73

MgO + FeO*

86
The Dynamic Crystallization of

Basalt

When the first basalts were returned

from the Moon, it was evident that they

were much like terrestrial basalts.

There were differences, however subtle, in both chemistry and texture. One

interesting difference was that the

roles of pyroxene and plagioclase in

the texture were reversed in some

rocks. In terrestrial basalts, certain textures are defined by a fretwork of

plagioclase laths enclosing either

glass or pyroxene (intersertal to intergranular). In some Apollo 11

basalts, pyroxene formed the fretwork

and plagioclase was interstitial or

poikilitic (enclosed the pyroxene).

This reversal is a direct result of a near

reversal in the model amounts of

pyroxene and plagioclase in the

basalt.

Some Apollo 12 and 15 basalts are

porphyritic basalts; i.e., large crystals

of pyroxene and/or plagioclase

enclosed in a finer grained matrix of

more plagioclase and pyroxene. This

was an important difference from the

Apollo-11 basalts because phenocrysts definitely indicated a more

complex preeruption history for the

basaltic magma, much like basalts on

Earth. The phenocrysts, however, were

not like those commonly seen in terrestrial basalts. They were skeletal to

dendritic and showed complex and

extensive chemical zoning. Such

features were not compatible with the

slow growth typically associated with

phenocrysts at depth in the Earth, but

rather implied that the crystals grew

rapidly on or near the lunar surface.

Experiments conducted in the experimental petrology laboratory at JSC

confirmed that the lunar porphyritic

basalts did indeed crystallize completely at or near the lunar surface.

The phenocrysts did not represent a

preeruption phase of the magma history. Continuation of those initial experiments has provided further insight into

the histories of lunar basalts and now

into terrestrial basalts as well.

One of the most important results of

this continued research is the effect of

heterogeneous nucleation on the subsequent textural development. When

cooled at the same rates from a complete liquid, terrestrial basalts do not

crystallize as readily as do lunar

basalts. This is another manifestation

of the chemical differences between

the two groups of basalts. The lunar

basalts are far less viscous and

therefore crystallize more readily.

Thus, it is for terrestrial basalts that the

presence of heterogeneous nuclei is

so important. These nuclei need not

be large and in most cases are below

the resolution of the ordinary

petrographic microscope. Their presence can be strongly argued,

however, based on the textures observed in the experiments.

Plagioclase, even though it is

usually the dominant mineral in terrestrial basalts, is the most reluctant

mineral to nucleate. In the basalt

studied most extensively, olivine is the

first mineral to appear on cooling

(1198 ° C), followed by plagioclase

(1187 ° C) and pyroxene (1133 ° C). If

the basalt is melted above the liquidus

at, e.g., 1215 ° C, so that all crystals

(whether visible or not) have melted

and then cooled at 2° C/hr, the product

contains only olivine and pyroxene in a

matrix of glass (fig. 1). The plagioclase

did not crystallize and its chemical

components are still contained in the

glass. If the basalt is melted at a lower

temperature so that not all the olivine

and plagioclase have melted before

cooling is initiated at the same 2 ° C

/hr, the resulting texture is very

different (fig. 2). The plagioclase is

well crystallized into elongate crystals

that are somewhat skeletal. The

plagioclase forms a fretwork and,

because the pyroxene is very finegrained, the texture is intersertal. To

obtain such radically different textures

at the same cooling rate helps to explain the greater variety of textures in

terrestrial basalts compared to those

on the Moon. This phenomena will

also help explain the existence of very

thick basalt flows on Earth that have

finer-grained textures than they should

have based on cooling rates that can

be predicted from thermal-cooling

models. Either a very high density of

preexisting nuclei or a total absence of

nuclei (should they be reluctant to

nucleate) will result in fine-grained

textures at slow cooling rates.

The study of the crystallization

behavior of rock magmas is continuing

with the hope that at some future time

the histories of rocks can be read from

their textures; i.e., the physical path

from their birth to their current resting

places as well as their chemical evolution.

Figure 1.--Basalt melted above the liquidus

so that all crystals have melted and then

cooled at 2° C/hr, resulting in a product

containing olivine and pyroxene.

Figure 2.mBasalt melted at a lower temperature so that not all the olivine and

plagioclase have melted before cooling,

resulting in a very different texture.

87
Antarctic Dry Valleys: Terrestrial

Analog of the Martian Surface

The Dry Valleys of Antarctica probably

represent the best terrestrial analog of

the surface of Mars. The Dry Valleys

are similar to the Martian surface in the

following manner: low temperatures

and humidities, diurnal freeze-thaw

cycles (even during daylight hours),

low annual precipitations, desiccating

winds, oxidizing environment, high

sublimation and evaporation rates,

high-radiation environments, tow

magnetic fields, absence of higher life

forms, and irregular distribution and

tow abundances of soil microorganisms. The Viking landers have shown

that the surface of Mars is similar to

those surfaces observed in the Dry

Valleys of Antarctica (fig 1).

In order to better study the properties

of planetary regoliths, a large suite of

soils, rocks, and cores was collected

from Wright and Taylor Dry Valleys located in southern Victoria Land, Antarctica. The suite of samples was collected using techniques developed for

collection of the lunar samples. Frozen

samples were returned to JSC and

their initial characterization is underway in the geoscience laboratories of

the Planetary and Earth Sciences

Division.

Preliminary findings indicate that the

samples collected from regions surrounding evaporite ponds show sulfur

abundances similar to those observed

on the Mars surface at both the Viking

1 and 2 landing sites. The soils are

enriched in sulfur (up to 4 to 6 percent) immediately beneath the surface and depleted above and below

the enrichment zone. It is believed

that the enrichment in sulfur represents deposition of evaporite minerals

during the percolation of ground

waters toward the surfaces. Similar

processes are believed to occur on the

Martian surface resulting in the salt

deposits observed by the landers.

Thus, there is good reason to expect

that further study of the collected suite

of Dry Valley soils will provide important information that will assist in the

understanding of the data returned

from the Viking landers.

Figure 1.--Surface observed in the Dry Valleys of Antarctica.

88
The Chemistry of

Micrometeoroids

A significant dust population exists in

the inner solar system, prominently

manifested, for example, by the zodiacal cloud, visible meteoroid showers,

and small-scale impact phenomena

on lunar surface materials. The origin

of these particles is of great planetary

interest and current studies include

time-of-flight spacecraft experiments,

astronomical observations, lunar

microcrater analysis, and dynamical

studies relating to the evolution of their

orbits.

The planetary interest is based primarily on the fact that a significant

fraction of these particles originated

from comets. Another prominent

source area may be the asteroid belt

and a small fraction may even be of interstellar origin. Each of the above

sources may yield materials that are

mineralogically and chemically

different from all other extraterrestrial

materials currently available for

analysis in terrestrial laboratories.

Although exact proportions of these

three sources in the makeup of the interplanetary dust population are presently unknown, it is generally agreed

that comets must be the major contributor. On close solar approach, comets release gases as well as solids; the

solids are manifested in "dust tails."

Because comets primarily consist of

frozen volatiles, they must have originated at different pressure/temperature conditions during solar

nebula condensation than did the inner planets, which are characterized

by relatively refractory elemental composition. Therefore, comparison of

cometary "solids" with materials from

the inner planets becomes fundamental in defining boundary conditions for

the early solar system.

The primary objective of the chemistry

of micrometeoroids experiment is to

characterize the chemical composition of interplanetary dust. Secondary

objectives focus on the total particle

flux and some selected physical properties such as the bulk density and

shape of individual particles.

Gold surfaces totaling approximately 10 square feet will be exposed

to the natural micrometeoroid environment onboard the Long Duration Exposure Facility (LDEF) (fig. 1). Upon

impact, the dust particles will create a

hypervelocity crater and remnants of

the projectile will reside in the crater

bottom. Upon return to Earth, these

projectile remnants will be analyzed

by a variety of microanalytical techniques. The primary reasons for using

gold as a collector surface consist of

the requirements to have a high-purity

substrate to maximize the signal-tonoise ratio during the analytical investigations and to have a chemically

inert substrate. Furthermore, a substrate material that is not an important

element in cosmochemical modeling

and meteorite studies had to be

selected. Finally, a ductile material retains proiectile remnants much more

efficiently than do brittle substances.

For an anticipated exposure time of

about 15 months, a total of approximately 50 microimpacts are expected, ranging in size from 20 to 100

micrometers in diameter; the projectile remnants may be as small as

10 -_° to 10 -_2 grams. They will be

analyzed primarily with scanning

electron microscopes and energy-dispersive X-ray techniques.

Assembly of the experiment is

completed. Parts of the flight acceptance tests were accomplished and the

experiment should soon be flightrated. The Long Duration Exposure

Facility launch is presently scheduled

for late 1984.

Figure 1.---Schematic layout of the chemistry of micrometeoroids experiment. A clamshell-type

arrangement is used to open and close the collector doors that house the gold plates. One

clamshell is illustrated in an open position; the second is in a closed position. Electronic sequencers will initiate opening and closing of the doors a few days after Shuttle deployment and

a few days before redocking for retrieval. This assures maximum protection from various contaminants during ground handling, launch, deployment, and retrieval. Part of one opened door

shows rows of small collectors made for experimental purposes. These collectors consist of

high-purity graphite, aluminum,beryllium, and various plastic products.

89
Remote Sensing of Lunar Rock

Composition by Infrared

Measurement

The existence of weak reststrahlen

bands in the 8- to 14-micrometer

spectrum of the Moon was demonstrated during the previous reporting

year. This past year, additional

measurements were made to verify

the results and to develop improved

methods for the detection of the weak

bands.

The best technique was found to be a

differential measurement. The

difference spectrum was measured

between two lunar sites when the

local lunar Sun angle was such that

they were at the same calculated temperature. In this way, spectral

differences between the two sites

were emphasized.

The difference spectrum between

the central peak of Tycho and the

Apollo 1t site is shown in figure 1,

along with a laboratory spectrum of a

feldspar-rich lunar soil sample.

Apollo 11 was chosen as a

reference site because the old glassrich powder at this site should have

few, if any, spectral features. Tycho is

a relatively fresh crater and young

crystalline rocks should be exposed

there. Hence, most of the structure in

the difference spectrum is assumed to

be from Tycho.

This lunar difference spectrum was

measured at a spectral resolution (1

centimeter -1 ) high enough to permit

the lunar continuum spectrum to be

seen between the water lines.

However, ozone lines are not resolved

at 1 centimeter -_ and the region

around 1050 centimeters-_ is completely screened by atntospheric

ozone.

Of particular interest in this

spectrum is the weak band near 820

centimeters -_. This band is not found

in bulk samples of feldspar but does

appear in feldspar powders when the

particle size is reduced below approximately 50 micrometers.

Thus, the lunar infrared spectra are

determined not only by mineral composition but also by particle size. More

laboratory and theoretical work on the

emission spectra of powdered

minerals is needed before lunar

spectra of this kind can be fully interpreted.

Figure 1 .---Spectrum of difference between two lunar sites.

DIFFERENTIAL

RADIANCE

W/cm2ster cm -1 x 10 6

2.0

1.8

1.6

1.4

1.2

1.0

.8

.6

.4

.2

0

750

ARONSON etal. (1979)

850 950 1050 1150 1250

WAVENUMBER or. -1

90
Advanced Hyperthermia System

The advanced hyperthermia system

was a joint program involving NASA

and the Stehlin Foundation for Cancer

Research. The objective of the project

was to employ NASA expertise toward

the development of an improved heating system that would be used by the

Foundation in the treatment of certain

types of cancer.

Over the years, it has been demonstrated that hyperthermia has been

successful in certain cancer therapies.

Tumor cells were found to be more

sensitive to killing than normal cells

when heat was applied. There is less

blood flow (for heat transport) in solid

tumors than in normal tissue, leading

to greater heating for these tumor

cells. Even partial regressions of

tumors were observed where they

were previously inoperable. The

Stehlin Foundation for Cancer

Research has been using hyperthermia over the past 15 years with dramatic results. However, the present

systems have several basic disadvantages. The Foundation solicited

NASA's support toward reducing or

eliminating these problems. Preliminary background efforts indicated that

NASA technology could be applied,

and the Foundation contributed funds

for the purchase of the necessary

hardware.

In mid-1978, JSC signed a

Memorandum of Understanding with

the Stehlin Foundation for Cancer

Research at St. Joseph's Hospital in

Houston, Texas, outlining the responsibilities of both organizations and

defining the technical support of JSC.

The challenge for JSC engineers

was to improve radiofrequency heating techniques used at the Stehlin

Foundation. The first step was to

develop a machine for treatment of

small animals (fig. 1). The smallanimal experimental system that was

developed provided valuable data on

applicator size and shape in addition

to determining tolerable temperatures.

A notable feature of the system was

the ability to apply up to 50 watts at

five frequencies from 3 to 30

megahertz. The small-animal system

also assisted in establishing human

protocols and studying the effects of

hyperthermia at the cell level.

After a year of tests on mice, JSC

developed an advanced radiofrequency hyperthermia system for treatment

of humans (fig. 2). Developing the

human system involved concern about

safe and reliable performance. A team

of engineers, scientists, and representatives of the JSC Safety, Reliability,

and Quality Assurance Division helped

monitor and review the overall design

and performance. In January 1980, the

team delivered an experimental

human treatment system to St.

Joseph's Hospital.

The radiofrequency system for

human treatment uses a gradual

buildup of power to a preselected

value. Two pairs of sequentially driven

electrodes provide more concentration

of radiofrequency power at the tumor

and disperse heat at the skin. A feedback control that allows regulation of

temperatures within a specific area to

an accuracy of 0.2 ° C was also

designed. One area of concern was

the heating of the skin below the

electrodes that, in some cases,

caused burns. The solution was to circulate temperature-controlled water

through metal tubing soldered onto the

back of flexible electrodes. A data

printer added to the system records

temperatures and power levels as a

function of time. The human radiofrequency system has been used successfully on several cancer patients.

Figure 1 ._mall-animal experimental

system. Figure 2.--Advanced radiofrequency hyperthermia system for treatment o! humans.

91
Linear Accelerator for Human

Vestibular Research

NASA has long been interested in

developing tests that assess the

effects of extended zero-gravity space

flight on the vestibular system of

flightcrews. On the basis of limited

flight data and fairly extensive groundbased laboratory data, it is widely accepted that alterations in the otolith

receptors of the inner ear are primarily

responsible for the vestibular disturbances (including space motion sickness) observed in about 40 percent of

U.S. astronauts and Soviet cosmonauts. Therefore, investigations of

otolith function, both in the terrestrial

and weightless space flight environments, will probably significantly

enhance our understanding of vestibular function in zero gravity. Such

studies should also provide insight

regarding the etiology of space sickness and contribute to the development of methods for controlling this

potentially debilitating syndrome.

Different testing procedures have

been used to apply meaningful stimuli

to the otolith receptors in man. These

include static tilt, the use of four-pole

swings, and short periods of altering gforces achieved with parabolic flight.

Although much can be learned by

these techniques, it is of great value to

use precisely controlled and programmable linear acceleration. It was with

this objective in mind that the

Neurophysiology Laboratory at JSC

elected in March 1978 to develop a

man-rated linear acceleration device

for ground-based vestibular research.

Dr. David Anderson of the Kresge

Hearing Research Institute at the

University of Michigan, because of his

experience in the design and fabrication of moving platform systems for the

measurement of posturat mechanisms

in man (fig. 1), was contracted to

design and develop a human linear

accelerator for use at JSC The linear

accelerator system was delivered to

JSC in June 1979. The system consists of several fundamental components. A platform upon which the subject seat or restraint system is located

rides on two parallel steel rods. The

platform is connected via a cabledrive assembly to a dc torque motor

mounted at one end of the frame. The

system incorporates an electronic

package that contains a power

transformer, a power supply, a servoamplifier, and a controller interface

for connection to a LSI-11 microprocessor. The frame of the accelerator is 12 feet long and 3 feet wide and

the displacement of the accelerator

platform is approximately 8 feet peakto-peak. It is capable of achieving accelerations up to 0.5g over a frequency

range of approximately 0.18 to 5.0

hertz. The accelerator can be programed to deliver constant g (ramp),

sinusoidal or.pseudorandom linear displacement. Following delivery to JSC,

the linear accelerator was "ruggedized" for use on the KC-135 zerogravity airplane and a number of subject/operator safety devices were

added. Several computer programs

have been written for controlling the

device in various operating modes.

Actual experimental use of this linear

acceleration system has been limited

during the period from July 1979 to the

present. During this time, considerable

effort was expended in implementing

the various system improvements previously defined and in conducting

various functional checkouts. The

system has also been used to conduct

pilot studies to evaluate the effects of

linear acceleration on vestibulo-spinal

reflexes in man. Plans for everincreasing use of the system will be

made to conduct linear acceleration

experiments with humans. These experiments will directly support the implementation of Spacelab 1 Experiment 1NS-104, "Adaptation of

Vestibuto-Spinal Reflex Mechanisms

During Space Flight," as will a similar

flight experiment tentatively planned

for the first dedicated life sciences

Spacelab. Certain phases of these

ground-based support experiments

will be conducted during parabolic

flight, representing the first time that a

precision linear acceleration device

has been flown in such an environment. The linear accelerator will also

be evaluated for its ability to evoke

symptoms of motion sickness. If early

studies of this type are successful, the

device will be increasingly used to

evaluate susceptibility to motion sickness and to evaluate the efficacy of

antimotion-sickness medications. In

general, the human linear acceleration

device has added a significant dimension to the JSC Neurophysiotogy

Laboratory's ability to investigate

vestibular function, especially otolith

receptor function in man.

Figure 1.-.-Linear accelerator system for human vestibularresearch.

92
Nuclear Cardiology Imaging

System

The multiwire proportional counter

(MWPC) is a modern instrument used

for detection of ionizing radiation. It is

widely used in research applications

for accurate high-speed position

measurements of ionizing radiation. A

sophisticated yet simple technique for

electronic readout of this instrument

was developed for space research at

JSC and is currently being adapted for

medical imaging applications. The

very high rate capability of this technique, combined with its simplicity

and low cost, offers the possibility of a

significant advance in certain areas of

nuclear medicine where high-speed

imaging of dynamic radioisotope distributions within the body is required.

A prototype device currently in operation at JSC has demonstrated this potential and a refined device is nearing

completion and should allow medical

testing on human subjects in 1981.

Applications of the JSC multiwire proportional counter in the field of nuclear

cardiology are particularly promising.

In the nuclear cardiology technique, a

radioactive tracer is injected and the

passage of the tracer through the heart

is viewed with the MWPC imaging

device. By making rapid sequential

images that are stored and manipulated by an on-line computer, the

device can obtain measurements of

great diagnostic value, such as determination of ventricular stroke volume

and ejection fraction and observation

of heart chamber wall motion irregularities.

The dynamic imaging capability of

the prototype device has been tested

using a cardiac phantom. This phantom was specially designed and constructed at JSC; it consists of a fluidfilled rubber bag with a volume that

can be rapidly modulated to simulate

the human left ventricle. Tests have

been conducted in which a radioactive

tracer was injected into the bag, which

was pulsed at 60 beats per minute

from a diastolic volume of 140

milliliters to a systolic volume of 0

milliliters. The MWPC camera was

used to produce 16 stop-action views

of the ,phantom (fig. 1). The radiation

intensities observed by the camera are

interpreted by using the color-coded

bar at the right. An on-line computer

was used to locate the wall perimeter

of the phantom. Computer software

has also been developed to determine

the stroke profile (volume versus time

correlation) and ejection fraction. The

accuracy of these measurements has

been validated for various ejection

fraction values, pulse rates, and stroke

volumes.

A method was recently developed

for production of a radionuclide

generator that provides a continuous

supply of the short half-life isotope

tantalum-178 (T_/2 = 9.3 min). This

makes possible the application of this

isotope as a nuclear medicine tracer.

Tantalum-178 is nearly optimum for

use with the multiwire proportional

counter. Tantalum's attractive intrinsic

features include its short half-life,

which permits repeat studies at short

intervals, and very low radiation exposure compared with currently used

clinical radionuclides. A 100-millicurie

tantalum-178 generator has been produced at JSC from tungsten-178 (the

generator parent isotope) which was

furnished by Lewis Research Center.

Eluent from this generator was used to

perform the phantom tests.

In addition to the MWPC application, tantalum-178 has potential application for use with commercially

available imaging devices if interference between its low-energy primary photons (54 to 65 kiloelectronvolts) and its less-abundant highenergy photons can be resolved. In

collaboration with Baylor College of

Medicine, good quality images have

been produced by tantalum-178 using

both multicrystal and Anger cameras.

These cameras are the imaging

devices most used in clinical nuclear

cardiology. The tantalum-178 studies

included static and dynamic imaging,

ejection fraction, and wall motion and

sensitivity measurements. The quantitative results have been compared

with those obtained using technetium-99. Technetium-99 (half life, 6

hr) is the commonly used radionuclide

in clinical angiocardiography studies.

Collaborative agreements have been

made with E R. Squibb Research Institute and Harvard Medical School to

test NASA-produced tantalum-178 to

improve the safety, reliability, and

yield of the tungsten-tantalum generators. These studies will validate the

use of tantalum in human studies with

particular emphasis on nuclear

medicine research uses.

It is expected that combined application of MWPC imaging technology and tantalum-178 to the

nuclear cardiology field will open new

areas of diagnostic capability and improve techniques already being extensively used with existing cameras and

isotopes.

Figure 1.--The MWPC camera produced these stop-action views of the phantom as it contracted and expanded through one cycle. (a) Radiation intensities observed by the MWPC

camera. (b) Wall perimeter of a cardiac phantom.

93
Mobile Biological Isolation

System

tn January 1974, a request was

received from the Baylor College of

Medicine outlining a need for a germfree suit system for use by a 2-1f2-

year-old child who was afflicted with a

severe immunization deficiency and

had lived in a germ-free carefully constructed room (bubble) since birth.

The objective of the ensuing program

was to develop a mobile biological

isolation system for use by patients

with immunization deficiency or

aplastic anemia or who were undergoing chemical therapy or organ

transplant, requiring their confinement

to laminar-flow isolation facilities.

The mobile biological isolation system

consists of a bioisolation unit or suit

assembly and a pushcart transporter

(fig. 1) that carries a life support

system. The mobile biological isolation system is divided into three subsystems: suit and air supply, mechanical, and electrical power.

The suit and pressure-retention assembly is of one-piece construction

and consists of a neoprene-coated

nonporous nylon bladder to which are

permanently attached a soft

transparent plastic helmet, rubber

gloves, and boots. The configuration

supplied to the Texas Children's Hospital, Baylor College of Medicine, includes a permanently attached tunnel

and adapter ring assembly that atFigure 1.--The mobile biological isolation system consists of a suit assembly, a pushcart

transporter, and a life support system.

94

taches directly to one of the patient's

isolation bubbles. This allows the patient to don and doff the suit without

ever coming in contact with the nonsterile outside environment or outer

surface of the garment. A 2-foot

sheath was fabricated on the back of

the garment. After subject entry, the

sheath is simply rolled shut and strapped in place.

A lightweight overgarment of

porous nylon (Nomex) -- similar to

that used in certain outer layers of the

Gemini space suit -- is worn over the

suit and affords additional protection

against abrasion, puncture, and fire.

The tunnel is sheathed with a material

identical to that used for the pressure

garment and this sheathed configuration serves as a tether during patient

excursions. Ambient air, filtered to 0.3

micrometer via a high-efficiency particle-accumulator filter, is blown into

the helmet by one of three (two redundant, one emergency backup) ventilator fan assemblies, circulated over the

body for cooling, and exited at the

ankles under positive pressure.

A typical lawnmower frame,

wheels, handles, and brakes serve as

the basic transporter unit on which

mechanical and electrical equipment

is mounted. A seat is provided

together with a swing arm to allow the

patient to ride on the transporter or to

walk alongside within the l O-foot

radius of the suit tunnel
The electricalpowersystemincludestwoblowers,twomotors,two

12-voltbatteries,andthecircuitryrequiredtoutilizepowerfromastandard

householdelectricaloutletora motor

vehiclecigarettelighter.Duringnormaloperation,thebatteriesareconnectedin parallel.Thesystemwas

designedto supporta 4-houroutside

excursionasaminimum(fig.2).Additionaltimeis permissibleaspatient

comfortandenduranceallow.(Additional emergencyequipmentand

reconfigurationoptionsareavailableto

thequalifiedoperator.)

Twonew largersuitsare being

developedfor the patientat Texas

Children'sHospitalandareexpected

tobecompletedbylate1980.Results

ofgrowthstudieswereincorporatedto

increasetheoverallweartimeof the

suits.Newmaterialsarebeingused

thatallowstrongerseamsandeasier

fabrication.Glovematerialhasbeen

changedfromneopreneto dipped

latextoallowgreatertactilityanddexterity.Bootsarenolongerpartof the

legassembly.Thenewconceptprovidesatubesockaspartofthelower

leg, allowingthe subjectroomfor

growthand permittinghim to wear

betterfittingshoesorsneakers. Anew

helmetmaterialanddesignincreases

opticalqualitiesandvisibility.Theairspraydesignisalsoimprovedtoallow

betterdispersionof carbondioxide

and to eliminatevisorfogging.The

outergarmenthasbeenredesignedto

giveacasualdenimlookwithpockets

largeenoughto accommodatemany

articles.Perhapsthegreatestimprovementisachangefromthepreviousexhaustportstoamorereliabletypethat

iseasilyreplaceable.

Figure 2.---Supported by the mobile biological isolation system, the patient is able to go on an excursion.

,r

NASA-JSC

• .

95
L_BRARY

l.js_

/

The charge-out number (Accession N

_or this book is _ ..--_ ,,/ ._ o._

MAR _ _,_i

OHNSON SPACE CEN]

HOUSTON, TEXAS