STS-66 PRESS KIT



           NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

                  SPACE SHUTTLE MISSION STS-66

                          PRESS KIT

                       NOVEMBER, 1994


ATMOSPHERIC LABORATORY FOR APPLICATIONS AND SCIENCE-3  (ATLAS 3)

CRYOGENIC INFRARED SPECTROMETERS AND TELESCOPES FOR THE ATMOSPHERE - 
SHUTTLE PALLET SATELLITE (CRISTA-SPAS)







PUBLIC AFFAIRS CONTACTS

For Information on the Space Shuttle

Ed Campion    Policy/Management              202/358-1778
  Headquarters, Wash., D.C.

James Hartsfield       Mission Operations    713/483-5111
  Johnson Space Center, Astronauts,  Houston

Bruce Buckingham  Launch Processing          407/867-2468
  Kennedy Space Center, Fla.         KSC Landing Information

June Malone  External Tank/SRBs/SSMEs        205/544-0034
  Marshall  Space Flight  Center, Huntsville, Ala.

Don Haley      DFRC Landing Information      805/258-3448
  Dryden Flight Research Center,  Edwards, Calif.

For Information on NASA-Sponsored STS-66 Experiments

Brian Dunbar            ATLAS-3              202/358-1547
  Headquarters, Wash., D.C.

Debra Rahn   International Cooperation       202/358-1639
  Headquarters, Wash., D.C.

Franz Spanhorst        CRISTA                011-49/228-447-545
  German Space Agency (DARA)
  Bonn, Germany

George Diller   SPAS                         407/867-2468
  Kennedy Space Center

Tammy Jones            ESCAPE                301/286-8955
  Goddard Space Flight Center

Mike Braukus                                 202/358-1979
  Headquarters, Wash., D.C      NIH-R-1, NIH-C-2, PCG, SAMS

James Cast     HPP                           202/358-1779
  Headquarters, Wash., D.C.




CONTENTS

GENERAL BACKGROUND
General Release                                 3
Quick-Look Facts                                7
Shuttle Abort Modes                             9
Summary Timeline                               10
Payload and Vehicle Weight                     13
Orbital Events Summary                         14
Crew Responsibilities                          16


CARGO BAY PAYLOADS & ACTIVITIES

Atmospheric Laboratory for Applications and Science-3 (ATLAS-3)   17
Cryogenic Infrared Spectrometers and Telescopes for the
Atmosphere-Shuttle Pallet Satellite (CRISTA-SPAS)(CRISTA-SPAS)    36
Experiment of the Sun for Complementing the Atlas Payload and for
Education-II (ESCAPE-II)                                          42


IN-CABIN PAYLOADS

National Institutes of Health-R-1                                 43
National Institutes of Health-C-2                                 48
Protein Crystal Growth (PCG) Experiments                          49
Space Acceleration Measurement System (SAMS)                      50
Heat Pipe Performance and Working Fluid Behavior in Microgravity 
         (HPP)                                                    51


STS-66 CREW BIOGRAPHIES

Donald (Don) R. McMonagle, Commander (CDR)                        52
Curtis (Curt) L. Brown, Pilot (PLT)                               52
Ellen Ochoa, Ph.D., Payload Commander/
    Mission Specialist-1 (MS-1)                                   52
Joseph (Joe) R. Tanner, Mission Specialist-2 (MS-2)               53
Jean-Francois Clervoy (ESA), Mission Specialist-3 (MS-3)          53
Scott E. Parazynski, M.D, Mission Specialist-4 (MS-4)             54




RELEASE:  94-175

ATMOSPHERIC LABORATORY MAKES THIRD FLIGHT


     NASA will continue to study how the Earth's environment is changing
and how human beings affect that change during the upcoming flight of
Space Shuttle Atlantis. STS-66, the third flight of the Atmospheric
Laboratory for Applications and Science (ATLAS), is part of NASA's Mission
to Planet Earth, a coordinated research effort to comprehensively study
the planet's environment.  Also during the STS-66 mission, astronauts will
deploy and retrieve a free-flying satellite designed to study the middle
and lower thermospheres and will perform a series of experiments covering
life sciences research and microgravity processing. 

     The STS-66 crew will be commanded by Donald R. (Don) McMonagle who
will be making his third Shuttle flight.  Curtis L. (Curt) Brown will
serve as pilot and will be making his second flight.  The four STS-66
mission specialists aboard Atlantis will include Ellen Ochoa, the STS-66
Payload Commander and Mission Specialist-1, who will be making her second
flight, Joseph R. (Joe) Tanner, Mission Specialist-2, Jean-Francois
Clervoy, Mission Specialist-3, and a European Space Agency astronaut, and
Scott E. Parazynski, Mission Specialist-4.  Tanner, Clervoy and Parazynski
will be making their first space flight. 

     Launch of Atlantis on the STS-66 mission is currently targeted for
Nov. 3, 1994 at 11:56 a.m. EST from Kennedy Space Center's Launch Complex
39-B.  After launch, the crew will work in two teams, each on 12 hour
shifts, making observations and collecting data with the experiments and
instruments being carried on the mission.  The mission is scheduled to
last 10 days, 19 hours, 46 minutes An on-time launch on Nov. 3 would
produce a landing at Kennedy Space Center's Shuttle Landing Facility on
Nov. 14 at 7:42 a.m. EST. 

     ATLAS-3 is the third in NASA's series of Atmospheric Laboratory for
Applications and Science Spacelab missions.  The remote sensing laboratory
studies the Sun's energy output, the middle atmosphere's chemical makeup,
and how these factors affect global ozone levels.  ATLAS-3's highly
calibrated instruments also will provide a check on similar instruments on
free-flying satellites, allowing scientists to determine how much those
instruments may have been degraded by the harsh environment of space. 

     Complementing the ATLAS science mission, the German-built Shuttle
Pallet Satellite (SPAS) which will carry two instruments -- the Cryogenic
Infrared Spectrometers and Telescopes for the Atmosphere (CRISTA) and the
Middle Atmosphere High Resolution Spectrograph Investigation (MAHRSI). 

     On Flight Day Two, the SPAS and its instruments will be deployed from
Atlantis using the Shuttle's mechanical arm.  The pallet will fly free of
the Shuttle as it observes a variety of gases in the middle atmosphere and
measures amounts of nitric oxide and hydroxyl in the middle atmosphere and
lower thermosphere.  Also onboard the satellite will be the small Surface
Effects Sample Monitor, a materials-science experiment aimed at measuring
decay of surfaces exposed to the near- Earth space environment. 

     For the retrieval of CRISTA-SPAS on the 10th day of STS-66, Atlantis
will use a new rendezvous approach to the satellite than has been standard
for past satellite retrievals.  The new approach is being evaluated for
use in rendezvous with the Russian Mir Space Station in 1995 due to the
propellant savings that it may achieve.  The new approach may not only
conserve propellant when approaching the Mir station but also could mean
less braking thruster firings are required during the rendezvous in
general, reducing risk of damaging Mir. 

     Also flying in the payload bay will be the Experiment of the Sun for
Complementing the Atlas Payload and for Education-II (ESCAPE-II ), a
student-designed and developed payload engineered to gather data that will
contribute to a better understanding of the Sun's radiative effects on the
Earth's upper atmosphere. 

     The ESCAPE II experiment was designed, managed and built entirely by
undergraduate and graduate students at the Colorado Space Grant Consortium
at the University of Colorado, Boulder.  ESCAPE II is expected to shed new
light on how the Sun's extreme ultraviolet wavelengths affect the
temperature and chemical composition of the upper atmosphere.  The release
of human-produced chlorofluorocarbons (CFCs), is believed to be largely
responsible for the recent seasonal decline in stratospheric ozone levels,
most markedly over the Earth's poles.  In order to understand the
magnitude of human-caused changes in the atmosphere, scientists first need
to measure the variability of natural solar radiation. 

     Two collaborative experiments developed by NASA and the National
Institutes of Health (NIH) will be part of the STS-66 mission.  The
NIH-R-1 payload is a developmental biology experiment consisting of 11
experiments that will study the effects of space flight on developing
rats.  These experiments will provide important insights into the fields
of gravitational and space biology and gravity's effects on living
organisms.  The NIH-C-2 payload is comprised of two biomedical experiments
that will make use of a computerized tissue culture incubator known as the
Space Tissue Loss (STL) Culture Module.  STL was developed at the Walter
Reed Army Medical Center in Washington, D.C., to study cells in
microgravity.  Both experiments will study the effects of space flight on
cells from chicken embryos. 

     The STS-66 mission will carry two related Protein Crystal Growth
(PCG) experiments -- the Crystal Observation System and the Vapor
Diffusion Apparatus.  These two experiments will continue research into
the structure of proteins and other macromolecules such as viruses. 
Proteins are important, complex biochemicals that serve a variety of
purposes in living organisms.  Determining their molecular structure will
lead to a greater understanding of functions in living organisms. 
Knowledge of the structure can also assist the pharmaceutical industry in
the development of disease-fighting drugs. 

     The Space Acceleration Measurement System (SAMS) will be flying for
the eleventh time during the STS-66 mission.  The middeck payloads that
SAMS is supporting are the PCG experiments.  SAMS will collect and record
data characterizing the microgravity environment in the Shuttle's middeck. 
SAMS will provide the scientists studying the PCG experiments with
information on the microgravity environment these crystals experienced
during the mission.  The scientists will be able to account for the rocket
thruster firings, crew activity and background vibrations that influence
these delicate experiments. 


     The Heat Pipe Performance-2 (HPP-2) Experiment will investigate the
thermal performance and fluid dynamics of heat pipes operating with
asymmetric and multiple heating zones under microgravity conditions. A
Thermal Performance Apparatus (TPA) mounted to middeck seat studs allows
the Orbiter crew members to test individual heat pipes in the crew
compartment during the flight. Thirty-five tests will be performed with
ten different axially grooved aluminum/freon heat pipes. 

     The design of effective spacecraft thermal control systems requires
an understanding of heat pipe fluid dynamics in a microgravity
environment. This behavior cannot be adequately evaluated on Earth because
gravity tends to dominate the capillary forces developed in the apparatus. 
For these reasons, flight experiments are critical for collecting the data
necessary for computer model validation. 

     The original Heat Pipe Performance Flight Experiment (HPP-1) was
flown on STS-52 in October, 1992, to investigate and document the
microgravity behavior and performance of several different types of heat
pipes. Data from HPP-1 was used to modify and validate a NASA heat pipe
computer model known as the Groove Analysis Program (GAP). The current
version of GAP models heat pipes with single and uniform heating and
cooling zones. The HPP-2 experiment will test heat pipes with asymmetric
and multiple heating zones, providing data for correlation with new
modifications to the GAP model. The basic difference between the two
experiments is that HPP-1 tested "ideal case," or simple heat pipes, while
HPP-2 will test more realistic heat
pipe designs that mirror the complexity of actual spacecraft 
applications.

     The end product of the HPP-1 and HPP-2 Flight Experiments will be a
GAP model capable of accurately predicting the performance of any type of
axially grooved heat pipe design prior to manufacture, so large costs
incurred by building and testing prototype heat pipes can be avoided. The
final version of GAP will allow thermal system engineers to be less
conservative in their designs, leading to fewer heat pipes per spacecraft,
thereby achieving significant weight and cost savings. 

     Shuttle Mission STS-66 will be the 13th flight of Atlantis and the
66th flight of the Space Shuttle system. 

                                - end general release -



STS-66 Quick Look

Launch Date/Site:                        Nov. 3, 1994/KSC Pad 39B
Launch Time:                             11:56 a.m. EST
Orbiter:                                 Atlantis(OV-104) - 13th Flight
Orbit/Inclination:                       165 nauticalmiles/57 degrees
Mission Duration:                        10 days, 19 hours, 46minutes
Landing Time/Date:                       7:42 a.m. EST November 14, 1994
Primary Landing Site:                    Kennedy Space Center, Fla.28
Abort Landing Sites:                     
Return to Launch Site -                  KSC, Fla.
TransAtlantic Abort landing -Zaragoza, Spain 
                             Moron, Spain
                             Ben Guerir, Morocco
Abort Once Around- White Sands Space Harbor, N.M.

Crew:                Don McMonagle, Commander (CDR)
                     Curtis Brown, Pilot (PLT)
                     Ellen Ochoa, Mission Specialist 1(MS1)
                     Joseph Tanner, Mission Specialist 2 (MS2)
                     Jean-Francois Clervoy, Mission Specialist 3(MS3)
                     Scott Parazynski, Mission Specialist 4 (MS4)

Red Team: McMonagle, Ochoa, Tanner
Blue Team: Brown, Clervoy, Parazynski

Cargo Bay Payloads:    Atmospheric Laboratory for Applications and 
                              Sciences-3 (ATLAS-3)
                       
                       Cryogenic Infrared Spectrometers and Telescopes
                              for Atmosphere/Shuttle Pallet Satellite 
                                            (CRISTA/SPAS)
                       
                       Shuttle Solar Backscatter Ultraviolet(SSBUV/A)
                       
                       Experiment of the Sun Complementing the ATLAS
                       Payload and Education-II (ESCAPE-II)

Middeck Payloads:      Protein Crystal Growth-Thermal Enclosure System
                                        (PCG-TES)
                       Protein Crystal Growth-Single Locker Thermal
                              Enclosure System (PCG-STES)
                       Heat Pipe Performance Experiment-Reflight 
                              (HPP-RFL)
                       Physiological and Anatomical Experiment/National
                              Institute of Health-Rodents (PARE/NIH-R)
                       Space Acceleration Measurement System (SAMS)
                       Space Tissue Loss-A (STL-A)




Development Test Objectives/Detailed Supplementary Objectives:
DTO 254:     Subsonic Aerodynamics Verification (part 2)
DTO 301D:    Ascent Structural Capability Evaluation
DTO 307D:    Entry Structural Capability Evaluation
DTO 312:    External Tank Thermal Protection System Performance
DTO 414:    Auxiliary Power Unit Shutdown Test (sequence A) 
DTO 623:    Cabin Air Monitoring
DTO 664:    Cabin Temperature Survey
DTO 668:    Advanced Lower Body Restraint Test
DTO 677:    Evaluation of Microbial Capture Device in Microgravity
DTO 680:    On Orbit Fit Check of the Recumbent Seating System on OV-104
DTO 683:    Interlimb Resistance Device Evaluation
DTO 700-2:  Laser Range and Range Rate Device
DTO 700-7:  Orbiter Data for Real Time Navigation Evaluation
DTO 805:    Crosswind Landing Performance
DTO 834:    Notch Filter
DTO 835:    Mir Approach Demonstration
DTO 836:    Tools for Rendezvous and Docking
DSO 484B:   Circadian Shifting in Astronauts by Bright Light
DSO 485:    Inter Mars Tissue Equivalent Proportional Counter
DSO 487:    Immunological Assessment of Crewmembers
DSO 493:    Monitoring Latent Virus Reactivation and Shedding in Astronauts
DSO 603:    Orthostatic Function During Entry, Landing and Egress
DSO 604:    Visual-Vestibular Integration as a Function of Adaptation
DSO 605:    Postflight Recovery of Postural Equilibrium Control
DSO 608:    Effects of Space Flight on Aerobic and Anaerobic Metabolism  
            During Exercise 
DSO 612:    Energy Utilization
DSO 614B:   The Effect of Prolonged Space Flight on Head and Gaze 
            Stability During Locomotion
DSO 621:    In-Flight Use of Florines to Improve Orthostatic Intolerance 
            Postflight
DSO 624:    Pre and Postflight Measurement of Cardiorespiratory Responses to 
            Submaximal Exercise
DSO 626:    Cardiovascular and Cerebrovascular Responses to Standing
            Before  and After Space Flight
DSO 901:    Documentary Television
DSO 902:    Documentary Motion Picture Photography
DSO 903:    Documentary Still Photography


SPACE SHUTTLE ABORT MODES

     Space Shuttle launch abort philosophy aims toward safe and intact
recovery of the flight crew, Orbiter and its payload.  Abort modes
include: 

* Abort-To-Orbit (ATO) -- Partial loss of main engine thrust late
enough to permit reaching a minimal 105-nautical mile orbit with
orbital maneuvering system engines.

* Abort-Once-Around (AOA) -- Earlier main engine shutdown with the
capability to allow one orbit around before landing at White Sands Space
Harbor, N.M. 

* TransAtlantic Abort Landing (TAL) -- Loss of one or more main engines
midway through powered flight would force a landing at either Zaragoza,
Spain; Moron, Spain; or Ben Guerir, Morocco. 

* Return-To-Launch-Site (RTLS) -- Early shutdown of one or more engines,
and without enough energy to reach Zaragoza, would result in a pitch
around and thrust back toward KSC until within gliding distance of the
Shuttle Landing Facility. 

     STS-66 contingency landing sites are the Kennedy Space Center, White
Sands, Zaragoza, Moron and Ben Guerir. 



STS-66 SUMMARY TIMELINE

Red/Blue Flight Day One
Ascent
OMS-2 burn (163 n.m. x 165 n.m.)

Red Flight Day One
ATLAS activation
RMS checkout
SPAS activation
Group B powerdown

Blue Flight Day Two
ATLAS operations
SSBUV activation
SSBUV operations

Red Flight Day Two
Group B powerup
CRISTA/SPAS checkout
CRISTA/SPAS deploy
CRISTA/SPAS separation
RMS payload bay survey
ESCAPE activation
Group B powerdown

Blue Flight Day Three
ATLAS operations
SSBUV operations

Red Flight Day Three
ATLAS operations
SSBUV operations
CRISTA/SPAS stationkeeping

Blue Flight Day Four
HPP operations
ATLAS operations
SSBUV operations

Red Flight Day Four
HPP operations
ATLAS operations
SSBUV operations
CRISTA/SPAS stationkeeping

Blue Flight Day Five
ATLAS operations
SSBUV operations

Red Flight Day Five
ATLAS operations
SSBUV operations
HPP operations
ESCAPE deactivation
CRISTA/SPAS stationkeeping

Blue Flight Day Six
ATLAS operations
SSBUV operations
HPP operations

Red Flight Day Six
ATLAS operations
SSBUV operations
HPP operations

Blue Flight Day Seven
ATLAS operations
SSBUV operations
HPP operations
CRISTA/SPAS stationkeeping

Red Flight Day Seven
ATLAS operations
SSBUV operations
CRISTA/SPAS stationkeeping
ESCAPE activation

Blue Flight Day Eight
ATLAS operations
SSBUV operations
HPP operations
ESCAPE deactivation

Red Flight Day Eight
ATLAS operations
SSBUV operations
HPP deactivation, stow
Half day off duty

Blue Flight Day Nine
ATLAS operations
SSBUV operations
Half day off duty
CRISTA/SPAS stationkeeping

Red Flight Day Nine
ATLAS operations
SSBUV operations
CRISTA/SPAS stationkeeping

Blue Flight Day Ten
ATLAS operations
SSBUV operations
Group B powerup
CRISTA/SPAS rendezvous

Red Flight Day Ten
CRISTA/SPAS proximity operations
CRISTA/SPAS grapple
CRISTA/SPAS deactivation/stow
Group B powerdown

Blue Flight Day Eleven
ATLAS operations
SSBUV operations
ESCAPE activation
Flight Control Systems checkout

Red Flight Day Eleven
ATLAS operations
SSBUV operations
RMS stow

Red/Blue Flight Day Twelve
ESCAPE deactivate, stow
Group B powerup
Cabin stow
ATLAS deactivation
SSBUV deactivation
Deorbit
Entry 
Landing


STS-66 VEHICLE AND PAYLOAD WEIGHTS

Vehicle/Payload                                      	Pounds

Orbiter (Atlantis) empty and 3 SSMEs                  	173,103

Atmospheric Laboratory for Applications and Sciences-3  8,287

Shuttle Solar Backscatter Ultraviolet                   893

CRISTA/SPAS (deployable)                                7,194

ESCAPE-II                                               747

Heat Pipe Performance experiment                        141

Physical and Anatomical Rodent Experiment-National
  Institutes of Health - R                              134

Protein Crystal Growth                                  250

Space Tissue Loss                                       57

Detailed Test/Supplementary Objectives                  175

Shuttle System at SRB Ignition                          4,508,369

Orbiter Weight at Landing                               209,857



STS-66 ORBITAL EVENTS SUMMARY

EVENT        START TIME         VELOCITY CHANGE             ORBIT
            (dd/hh:mm:ss)      (feet per second)                   

OMS-2        00/00:39:00            262 fps                163 x 165

SPAS deploy  00/19:52:00             n/a                   162 x 165

Sep 2        00/20:09:00            1 fps                  165 x 162

    NC1      00/23:11:00            0.4 fps                165 x 162

    NC       1/17:18:00             2.8 fps                164 x 165

    NC3      01/21:50:00            3.3 fps                162 x 165

    NC4      02/14:27:00            1.2 fps                162 x 165

    NC5      03/01:01:00            TBD                    162 x 165

    NC6      03/07:04:00            .2 fps                 162 x 165

    NC7      04/01:11:00            1.2 fps                163 x 165

    NC-8     04/11:46:00             TBD                   162 x 165

    NC-9     04:17:48:00            2.4 fps                161 x 165

    NC-10    05/08:55:00             TBD                   161 x 165

    NC-11    05/19:30:00            .7 fps                 162 x 165

    NC-12    06/00:02:00             TBD                   162 x 165

    NC-13    06/15:08:00            .2 fps                 161 x 166

    NC-14    07/13:49:00            .2 fps                 161 x 165

    NC-15    08/01:55:00             TBD                   161 x 165

    NC-16    08/08:32:00             TBD                   162 x 165

    NC-17    08/13:11:00             16 fps                162 x 166

    NH       08/13:56:00             1 fps                 162 x 175
             
    NCC-1    08/15:15:00             TBD                   160 x 161

    MF       08/16:12:00             10 fps                160 x 161

    NCC-2    08/16:46:00              TBD                  161 x 161

    TI       08/17:43:00             9 fps                 161 x 165

    GRAPPLE  08/20:09:00              n/a                  161 x 165

    DEORBIT  10/18:46:00             265 fps                  n/a

    LANDING  10/19:46:00               n/a                    n/a

NOTES:

1. All maneuvers are recalculated in real time based on actual tracking
and the orbiters navigation. Many times and total velocities may change.
Some burns may be deleted. 

2. NC-1 through NC-16 are stationkeeping burns that serve to keep
Atlantis at 20-40 nautical miles ahead of CRISTA-SPAS.

3. NC-17 will move Atlantis from a point about 20 nautical miles ahead of
CRISTA-SPAS to a point about 20 nautical miles trailing CRISTA- SPAS. 

4. The MAHRSI Football (MF) burn will occur when Atlantis is about 8
nautical miles behind the CRISTA-SPAS and take Atlantis as close as 3
nautical miles to CRISTA-SPAS during one orbit for observations of the
shuttle by CRISTA-SPAS. The final phase of the rendezvous will occur when
Atlantis is again about 8 nautical miles behind CRISTA-SPAS with the
Terminal Phase Initiation (TI) burn, putting Atlantis directly on a course
over one orbit for the retrieval. 



STS-66 CREW RESPONSIBILITIES

TASK/PAYLOAD          PRIMARY                  BACKUPS/OTHERS

ATLAS-3                 Ochoa (red)            Parazynski (blue)
CRISTA-SPAS             Ochoa (red)            Clervoy (blue)
SSBUV                   Ochoa (red)            Parazynski (blue)
ESCAPE                  Parazynski (blue)      Ochoa (red)

Middeck Payloads:

HPP                Clervoy (blue)               McMonagle, Ochoa (red)
NIH-R              Tanner (red)                 Parazynski (blue)
PCG-TES            Tanner (red)                 Parazynski (blue)
PCG-STES           Tanner (red)                 Parazynski (blue)
SAMS               Brown (blue)                 McMonagle (red)
STL                Brown (blue)                 Ochoa (red)

Detailed Supplementary/Test Objectives:

DTO 664 (cabin temp.)       Brown              Tanner
DTO 677 (microbial)         Parazynski         Ochoa
DTO 668 (lower restraint)   Ochoa              Clervoy, Tanner
DTO 680 (seats)             Clervoy            McMonagle
DTO 683 (resistance dev.)   Parazynski         Tanner
DSO 608 (exercise)          Brown
DSO 624 (exercise)          McMonagle          Tanner
DSO 603B (orthostatic)      Clervoy            Parazynski

Other:

Photography/TV              Parazynski         Tanner
In-Flight Maintenance       Brown              Tanner
Earth Observations          Brown              Tanner
RMS                         Ochoa              Clervoy
Medical                     Parazynski         Ochoa



ATMOSPHERIC LABORATORY FOR APPLICATIONS AND SCIENCE-3 (ATLAS-3)

     ATLAS 3 is the third in NASA's series of Atmospheric Laboratory for
Applications and Science Spacelab missions.  The remote sensing laboratory
studies the Sun's energy output, the middle atmosphere's chemical makeup,
and how these factors affect global ozone levels.  ATLAS 3's highly
calibrated instruments will also provide a check on similar instruments on
free-flying satellites, allowing scientists to determine how much those
instruments may have been degraded by the harsh environment of space. 

     The ATLAS flights are part of NASA's Mission to Planet Earth, a
long-term, coordinated research effort to study the Earth as a single,
global environment.  Mission to Planet Earth's main focus is studying how
the global environment is changing and how human beings affect that
change. 

     The overall ATLAS 3 science mission includes six experiments on the
ATLAS pallet and a seventh on the wall of the Space Shuttle payload bay. 
Complementing the ATLAS payloads, the German freeflying science satellite
CRISTA-SPAS is comanifested as a prime payload. 

This satellite carries the German CRISTA telescope and the U.S. instrument
MAHRSI.  CRISTA-SPAS will be deployed and retrieved during the STS-66
mission and is controlled from Kennedy Space Center.  It is the second
mission in a series of at least four flights of the reusable science
satellite ASTRO-SPAS covered by a Memorandum of Understanding between NASA
and the German Space Agency DARA. 

     ATLAS 3's seven instruments, which flew on ATLAS 1 in March 1992 and
ATLAS 2 in April 1993, will again focus on the processes that affect ozone
levels.  A thin layer of ozone, between 6 and 20 miles high in the
atmosphere, shields life on Earth from most of the Sun's harmful
ultraviolet radiation.  However, in recent years ozone depletion has been
observed in both the Southern and Northern hemispheres, the most notable
example being the ozone "hole" that forms over Antarcticain September and
which can persist into December. 


     Ozone is created and destroyed by complex reactions involving
ultraviolet radiation from the Sun and gases in the middle atmosphere. 
While some of those gases occur naturally, concentrations of destructive
chemicals are increasing due to human activity.  To fully understand the
many factors that drive atmospheric chemical reactions and to predict
changes, scientists must have a comprehensive knowledge of the gases which
make up the atmosphere.  In addition, they must have precise data on the
Sun's energy output as it fluctuates. 

     The first two flights gathered a large number of global atmospheric
measurements at many different altitudes and measured changes in the Sun's
total energy output.  No other collection of space-based instruments gives
the range of atmospheric measurements provided by those of the ATLAS
payload. 

     Among other accomplishments, ATLAS 1 measured at various altitudes
the concentrations of chemicals resulting from the breakdown of industrial
compounds called chlorofluorocarbons (CFCs).  These observations are the
most direct confirmation that CFCs are the source of increased chlorine in
the atmosphere.  ATLAS 2 measured middle atmospheric ingredients over high
northern latitudes during daylight hours, helping scientists understand
the atmosphere's behavior following a winter of record-low ozone levels. 
Indications are that total ozone decreased by 10 percent at mid-latitudes
in the Northern Hemisphere during the period between ATLAS 1 and ATLAS 2. 

     ATLAS 3 will make detailed measurements over the Northern Hemisphere
in the late fall, allowing scientists to study important, but poorly
understood, processes as the atmosphere shifts from relatively quiet
summer conditions to more active winter conditions.  Investigators also
will study the chemical processes occurring in and near the Antarctic
ozone hole, which usually peaks in early October.  Observations of both
areas should provide valuable data for comparison with the spring data of
ATLAS 1 and 2. 

    The Space Shuttle is an ideal platform for NASA's remote-sensing
atmospheric laboratory.  The flight crew can maneuver the Orbiter so the
instruments in the bay point precisely toward the atmosphere, the Sun or
the Earth's surface.  The Shuttle's generous payload capacity and power
supply allow a diverse assembly of large instruments to make simultaneous
observations. Another advantage of flying aboard the Shuttle is the
ability to calibrate the Atlas instruments before and after flight,
offering more insight to scientists.  ATLAS instruments make more detailed
measurements than similar ones now flying aboard satellites. 

Satellite Underflights

     An important goal of the ATLAS program is to provide measurements
that relate to, and coincide with, those of instruments flying on
satellites.  ATLAS data is being used to refine existing ozone information
and to measure satellite instrument degradation caused by exposure to
ultraviolet radiation and particles including atomic oxygen.  Since the
Shuttle missions are short, any drift in instrument accuracy should be
small and can be determined once the Shuttle instrument is back on Earth. 

     On previous flights, all the ATLAS experiments achieved correlative
measurements with instruments on free-flyers such as the Upper Atmosphere
Research Satellite (UARS), NOAA meteorological satellites, the Earth
Radiation Budget Satellite (ERBS), and the European Retrievable Carrier
(EURECA).  Coincident measurements also were made with Total Ozone Mapping
Spectrometers (TOMS) on the Nimbus- 7 and Meteor-3 satellites. 

INSERT GRAPHICS A

ATLAS Atmospheric Science

     ATLAS 3's atmospheric science goals continue from the previous
missions:  measuring global, middle-atmosphere temperatures and trace-gas
concentrations and providing these measurements to the science community
for comparisons with those of other spacecraft.  In addition, because of
factors such as time of year, orbital lighting conditions, current state
of knowledge of the atmosphere, and new instruments, some goals are unique
to the ATLAS 3 mission.  When ATLAS 3 launches, atmospheric instruments
will examine the response of the Southern Hemisphere to the Antarctic
ozone hole and the change in Earth's northern middle atmosphere from
summer to winter conditions.  Also, the presence of two additional
instruments on a free-flying satellite will enhance the ATLAS atmospheric
data, providing more information on gas concentrations, including details
of their physical distribution. 

The ATLAS Instruments

     Atmospheric Trace Molecule Spectroscopy (ATMOS).  Principal
Investigator:  Dr. Michael R. Gunson, NASA Jet Propulsion Laboratory,
Pasadena, Calif. 

     The Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment will
measure the concentrations of more than 30 gases in the middle atmosphere. 
These measurements will be compared with those from previous ATLAS flights
to identify and characterize changes in the atmosphere's chemical
composition. 

     As the Shuttle's orbit carries the spacecraft in and out of Earth's
shadow (orbital night), the ATMOS instrument views the Sun as it rises or
sets through the atmosphere.  The spectrometer measures changes in the
infrared component of sunlight as the Sun's rays pass through this segment
of atmosphere, called the Earth's limb.  Because trace gases absorb at
very specific infrared wavelengths, the science team can determine what
gases are present, in what concentrations, and at what altitudes by
identifying the wavelengths that are "missing" from their data. 

     During the ATLAS 3 mission, the ATMOS instrument will have a
video camera to record pictures of the Sun during the sunrises and
sunsets, confirming the instrument's pointing.  The ATMOS recorder also
will have an improved controller, designed to give ground scientists more
information about the recorder's status and condition. 

     Changes in the atmosphere have been observed over the years, but the
causes and effects of those changes are not fully understood.  A more
thorough knowledge of which gases are present, and of how their
concentrations change over time, can help scientists determine if the
alterations are man-made, natural or a combination of both. 

INSERT B

     During ATLAS 1, ATMOS obtained atmospheric measurements over
latitudes between 30 degrees North and 55 degrees South.  These
measurements were compared to those collected over the same areas by ATMOS
during the Spacelab 3 Shuttle flight in 1985 to determine changes in the
amounts of industrial CFCs released and to study their conversion into
inorganic chlorine.  Results indicate an increase in inorganic chlorine
from 2.77 to 3.44 parts per billion, with a rise in fluorine from 0.76 to
1.23 parts per billion.  The fluorine increase confirms that the source of
the increased chlorine levels is industrial CFCs. 

     The ATLAS 1 mission occurred only nine months after the eruption of
the Mount Pinatubo volcano, the largest such event this century.  ATMOS
was able to measure changes in the components of the middle atmosphere
resulting from the presence of a thick layer of tiny droplets of sulfuric
acid formed from sulfur dioxide emitted by the eruption.  Scientists are
presently working to determine if the ozone loss in the Northern
Hemisphere in 1992-1993 was a direct result of an imbalance in the middle
atmosphere's chemistry caused by the Mt. Pinatubo emissions. 

     The night launch of ATLAS 2 allowed the ATMOS instrument to
complement ATLAS 1 measurements by extending the area of observations to
include Northern Europe, Siberia, Alaska and Canada at sunrise.  It
enabled scientists to study a large remnant of the polar vortex, a mass of
cold air normally isolated from lower latitude air by strong winds that
circulate around the North Pole in winter.  Quite different conditions
exist inside and outside this area. 

     During the early-spring flight of ATLAS-2, conditions outside the
vortex appear to have returned to normal, although with slightly higher
ozone levels.  However, the amount of chlorine nitrate, a key
chlorine-carrying gas, remained surprisingly high inside the vortexan
important indication of the earlier ozone depletion in this region. 
Scientists believe these conditions are part of the processes that lead to
the loss of ozone in polar winter and spring.  Further analysis of ATLAS-2
data should help clarify details of the important changes that occur
during this complex period. 

     ATMOS is a single assembly mounted on the Spacelab pallet in the
Space Shuttle's cargo bay.  Within the assembly are the Sun tracker,
detector, thermal control and electronics assemblies.  The experiment will
operate during the orbital sunrises and sunsets during the Earth viewing
portions of the mission, observing sunrises at high southern latitudes and
sunsets spanning the northern tropics through the mid- latitudes. 


     Millimeter-Wave Atmospheric Sounder (MAS).  Principal Investigator:
Dr. Gerd K. Hartmann, Max Planck Institute for Aeronomy,
Katlenburg-Lindau, Germany

     The Millimeter-Wave Atmospheric Sounder (MAS) measures the
distribution of water vapor, chlorine monoxide and ozone at altitudes
between 12 and 60 miles (20 to 100 km). 

      Chlorine monoxide, formed mainly by the breakdown of CFCs in the
middle atmosphere, plays an important part in ozone loss.  This compound
is produced when CFCs meet ultraviolet radiation in the upper atmosphere
approximately 3 to 5 years after their release into the air at the Earth's
surface.  CFCs come from sources such as coolants in refrigerators and air
conditioners, from foam containers and from halons, chemical compounds
often used in fire extinguishers.  The harmful effects of these products
were not foreseen when the chemicals were first put into use. 

     MAS measures the strength of millimeter waves, or waves of
frequencies between 30 and 300 gigahertz, radiating at the specific
frequencies of water vapor, chlorine monoxide and ozone.  With a new
chlorine monoxide receiver that is twice as sensitive as the one that flew
on the ATLAS 1 and 2 missions, MAS will attempt to better measure chlorine
monoxide and ozone over the upper latitudes of both hemispheres.  Also,
investigators plan to examine the evolution and/or breakup of the
Antarctic vortex, the mixing of polar and mid-latitude air and other
atmospheric changes occurring in the Southern Hemisphere. 

     Global information about ozone and chlorine monoxide helps provide
answers to the problem of human influences on the ozone layer, and MAS
therefore serves as part of an early warning system to determine how
widespread the destruction of ozone really is. 

     MAS results from ATLAS-1 agreed with theoretical expectations and
calculations. For example, a large daylight-to-dark ozone variation was
observed at heights above 43 miles (70 km), with much greater quantities
on the night side of the Shuttle's orbit.  Also, the varied quantities of
water vapor measured in the middle atmosphere are consistent with expected
results. 

     The ATLAS 2 night launch made it possible for MAS investigators to
observe ozone in Earth's middle atmosphere at high latitudes in both the
Southern and Northern hemispheres.  Chlorine monoxide, a key gas in ozone
destruction, was measured over the northern latitudes during the daylight. 
The daily changes in ozone concentration, including increased nighttime
ozone at high altitudes, were observed over the southern latitudes.  The
MAS instrument also measured water vapor, an excellent indicator of
atmospheric movement.  ATLAS 2 data confirm that upward atmospheric
movement occurs over the equator and downward atmospheric movement over
the poles during the spring equinox, the time of the mission. 

INSERT C

     MAS, mounted on the Spacelab pallet, uses a dish-shaped antenna to
scan Earth's limb (the far horizon) to collect spectral information at
distinct altitudes.  By measuring the strength of the microwave
radiations, scientists can deduce concentrations of ozone, chlorine
monoxide, water vapor and temperature. 

     Shuttle Solar Backscatter Ultraviolet Spectrometer (SSBUV). 
Principal Investigator:  Mr. Ernest Hilsenrath, NASA Goddard Space Flight
Center, Greenbelt, Md. 

     SSBUV provides accurate, reliable readings of global ozone to verify
the reliability of ozone information gathered by satellite instruments
which are in orbit for extended periods of time.  Scientists compare SSBUV
data with observations from National Oceanic and Atmospheric
Administration's NOAA-9 and NOAA-11 and NASA's Ultraviolet Atmospheric
Satellite.  The same atmospheric location is mapped by the UARS, SSBUV,
Total Ozone Mapping Spectrometer (TOMS) aboard the Russian Meteor-3
Satellite and NOAA instruments within 60 minutes up to 17 times a day. 

     SSBUV has flown on the Space Shuttle six times since 1989, including
the ATLAS 1 and 2 missions. The instrument detected and verified a
decrease in ozone of approximately 10 to 15 percent in the northern and
mid-latitudes of the Northern Hemisphere between ATLAS 1 and 2.  This
decrease was observed at the same time by satellites and through
ground-based observations. 

     The instrument also made solar observations, which were compared with
those made by the instrument on previous flights, and with solar
observations made by UARS instruments and other ATLAS investigations. 
Recent comparisons with the UARS and ATLAS solar measurements indicate
that the precision of the solar measurements made by SSBUV is at least
five times better than measurements made before the ATLAS mission. 

     During ATLAS 2, controllers used SSBUV's ability to focus on specific
wavelengths to look for nitric oxide.  They further refined the procedure
during STS-62 in March 1994, the instrument's last flight, to measure
nitric oxide during five orbits.  Measurements of sulfur dioxide in the
lower stratosphere were also attempted. 

     The SSBUV spectrometer is located in a Get-Away-Special canister,
attached to the side of the Shuttle's cargo bay.  A motorized door
assembly opens up to allow the SSBUV to view the Earth and Sun, and then
closes to protect the instrument from contamination when it is not in use. 
Data, command and power systems are housed in an adjacent interconnected
canister. 

      SSBUV measures solar radiation in 12 ultraviolet wavelengths that
scatter back from the atmosphere.  Variations in the 12 wavelengths of
backscattered radiation indicate how the ozone is distributed by altitude. 
Ozone absorbs shorter wavelengths of ultraviolet radiation more strongly
than it does longer ones.  Shorter wavelengths of ultraviolet radiation
are backscattered from higher altitudes, while longer wavelengths move
deeper into the atmosphere and are scattered from lower levels. 

Solar Science

     Sunlight provides the energy for many atmospheric processes; yet, the
Sun's radiant output fluctuates over an 11-year cycle, from a maximum to a
minimum and back again.  Within this 11-year cycle are the short-term
variations of the 27-day solar rotation period.  Earth's atmosphere is
influenced by both cycles, especially by variations in ultraviolet
radiation.  By gathering nearly simultaneous data on the Sun and the
atmosphere, scientists hope to identify and quantify the connections
between variations in solar energy and changes in the atmosphere. 

     The absolute value of the solar irradiance is one of the critical
factors that, in combination with Earth's absorption and reflection of
that radiation, determines the energy balance that governs the circulation
of the atmosphere.  More accurate measurements of the value of the solar
irradiance are needed and can be made only from above the densest layers
of Earth's atmosphere. 

     The first ATLAS flight occurred just after the beginning of solar
cycle 22, a time of near-maximum solar activity.  ATLAS 2 experienced a
Sun without sunspots during the last half of the mission.  Investigators
expect even less solar activity for ATLAS 3 as the cycle continuestoward
minimum activity, expected to occur in 1996-97.  The STS-66 crew will turn
the Shuttle's cargo bay toward the Sun four times during the mission, for
solar viewing periods lasting from six to eight orbits. 

     The Active Cavity Radiometer Irradiance Monitor (ACRIM).  Principal
Investigator:  Dr. Richard C. Willson, NASA Jet Propulsion Laboratory,
Pasadena, Calif. 

     The primary objective of ACRIM is to determine the degree and
direction of possible variations in the Sun's total output of energy, or
irradiance ACRIM measures the total solar irradiance from ultraviolet
through infrared wavelengths to better than 0.1 percent precision. INSERT
D

     As part of a long-term program to study the physical behavior of the
Sun and its effect on Earth's climate, NASA is putting together a highly
precise collection of information on solar irradiance.  For more than 20
years, the total solar irradiance has been monitored by instruments
orbiting on spacecraft such as Nimbus-7, the Solar Maximum Mission and
UARS.  An ACRIM instrument flew on Spacelab 1 (1983), the Solar Maximum
Mission (1980-1989), UARS (1991- ) and on ATLAS 1 and ATLAS 2. 

     During ATLAS 2, the instrument collected 25 orbits of observations
and made measurements that coincided with UARS' ACRIM.  Investigators
noticed outstanding instrument performance and highly precise
measurements.  Measurements were improved because the Sun was in a very
quiet period during the mission, allowing for possibly the most stable
calibrations ever achieved between the two instruments. 

      Through successive comparisons, the accuracy of the satellite
measurements can be maintained.  These instruments will help establish the
total solar radiation scale for the International System of Units.  By
comparing measurements of the solar constant made during ATLAS 3,
scientists can further refine the accuracy of this scale. 

     ACRIM , located on the ATLAS 3 platform, contains four cylindrical
bays.  Three of the bays house independent heat sensors, called
pyrheliometers, which are self-calibrating and automatically controlled. 
The fourth bay holds a sensor that measures the relative angle between the
instrument and the Sun. 

     Measurement of the Solar Constant (SOLCON).  Principal Investigator: 
Dr. Dominique Crommelynck, Belgian Royal Institute of Meteorology,
Brussels, Belgium

     SOLCON measures the absolute value of the total solar irradiance and
detects and measures long-term variations that may exist in its absolute
value.  The accuracy of the instrument allows the science team to
determine the value of the solar constant during a particular mission to
within 0.1 percent accuracy and about 0.01 percent precision. 

     Scientists theorize that systematic changes of only 0.5 percent per
century in total solar energy reaching the Earth could explain the entire
range of past climate changes from tropical to ice age conditions.  The
ATLAS solar instruments are designed to measure the changes in irradiance
to a long-term accuracy of 0.1 percent.  Continuous, more accurate
measurements of the solar constant will allow future generations to
identify solar and climatic trends over the centuries. 

     By comparing measurements of the solar constant from SOLCON and
ACRIM, as well as those from free-flying satellites, scientists can
continue to refine the accuracy of the total solar radiation measurements. 

INSERT E

     SOLCON flew on Spacelab 1 (1983), ATLAS 1 and ATLAS 2.  A copy,
called SOVA 1, also flew on the European Space Agency's European
Retrievable Carrier (EURECA), launched from the Shuttle in July 1992 and
retrieved in June 1993.  Preliminary results from ATLAS 1 indicate the
number of solar spots on the rotating solar disc influences the
fluctuation of the solar irradiance value. 

     The ATLAS 2 mission provided 26 orbits of operations and measurements
that coincided with SOVA 1.  These measurements were taken during a very
quiet period of solar cycle 22.  As with ACRIM, this situation provided
the best possible scenario for observations and comparison of the
instrument's radiometers.  Analysis of the data indicates that the
measurements made by SOLCON and SOVA 1 agree very closely on each of their
two channels regarding the approximate value of the solar constant as 1367
watts per square meter. 

     SOLCON is a high-resolution, self-calibrating radiometer with a
digital processing/converter unit.  The only part of the experiment that
is not automatic is the pointing operation, which requires that the
investigators analyze values obtained from a Sun sensor and, if necessary,
request minor changes in the orbiter's attitude that will correctly
position the experiment to point directly at the Sun. 

     The majority of SOLCON commands will be issued from the Space Remote
Operations Center in Brussels, Belgium, but the principal investigator
will be in Huntsville to participate in science planning.  About half of
SOLCON's operations during ATLAS 2 were commanded remotely from Brussels. 
This was a significant test of technologies that will be used for future
space operations. 

    Solar Spectrum Measurement from 180 to 3,200 Nanometers (SOLSPEC). 
Principal Investigator:  Dr. Gerard O. Thuillier, Aeronomy Service of the
National Center for Scientific Research, Verrieres-le- Buisson, France

     The objectives of SOLSPEC are to measure the absolute spectral solar
irradiance with the highest accuracy possible and to measure the
solarvariability at different times during a solar cycle. 

     Although most solar energy is contained in the visible and infrared
light that reaches the Earth's surface, the energy present in ultraviolet
and shorter wavelengths can vary significantly during an 11-year solar
cycle.  This variation can change the amount of energy reaching the
atmosphere, driving changes in the middle and upper atmospheres. 
Investigators want to identify regions in the atmosphere that are likely
to respond to particular changes in solar infrared, visible, and
ultraviolet ranges.  More simultaneous solar and atmospheric data will
improve our understanding of atmospheric processes and, eventually, our
ability to predict atmospheric behavior. 

INSERT F

     SOLSPEC flew on Spacelab 1, and it was part of both ATLAS 1 and ATLAS
2.  During ATLAS 1, SOLSPEC made observations of the light backscattered
by the ozone layer.  The preliminary analysis of SOLSPEC data indicates
that the values for ultraviolet, visible and infrared light are close to
the expected values, which will be helpful in validating scientists'
models showing the interaction of sunlight with the atmosphere.  These
measurements were compared to those taken by SSBUV and SUSIM.  The total
irradiance measured was compared with that measured by the SOLCON and the
ACRIM. 

     During ATLAS 2, SOLSPEC operated through 26 orbits and obtained
measurements that coincide with those from similar instruments on EURECA
and UARS.  Analysis of the data is continuing, and correlation between
ultraviolet and solar constant changes is being studied in great detail. 

     Investigators also had an important opportunity to study solar
variability when the activity level of the Sun decreased from the
beginning to the end of the ATLAS 2 mission.  ATLAS 2 data agree with data
gathered during ATLAS 1, and both sets of data have a greater degree of
accuracy than those obtained during Spacelab 1.  ATLAS 1 and ATLAS 2
results differ at certain wavelengths, and this dissimilarity demonstrates
the difference in solar activity during the two missions. 

     SOLSPEC, located on the ATLAS 3 pallet, has an onboard calibration
device and three double spectrometers that record solar radiation.  Once
in orbit, the SOLSPEC equipment is closely monitored by scientists at the
Spacelab Mission Operations Control center in Huntsville, Ala., during the
first calibration.  Later calibrations and observations are controlled
through the onboard equipment computer.  Some commands will be sent from
the remote center in Brussels. 

     Solar Ultraviolet Spectral Irradiance Monitor (SUSIM).  Principal
Investigator:  Dr. Guenter Brueckner, Naval Research Laboratory,
Washington, D.C. 

     SUSIM has two purposes. First, it measures the fluctuation of the
Sun's ultraviolet radiation.  During an 11-year solar cycle, changes in
ultraviolet radiation bring about changes in atmospheric conditions, such
as the amount of ozone in the stratosphere.  A better record of the Sun's
ultraviolet output will help scientists distinguish between atmospheric
changes caused by variations in ultraviolet radiation and those brought
about by human activity. 

     Second, SUSIM determines how much the ultraviolet light being
measured degrades the accuracy of the measuring instrument.  Unless the
extent of degradation is known, it is impossible to distinguish real
changes in solar radiation from the loss of accuracy in the instrument. 

INSERT G

     SUSIM operates during the Shuttle's solar-pointing periods to
establish a new and more accurate database on solar ultraviolet irradiance
(that portion of ultraviolet energy that reaches the top of Earth's
atmosphere) over a wide range of wavelengths, from 110 to 410 nanometers. 
Measurements of radiation in these wavelengths are almost completely
absorbed in the middle and upper atmosphere, preventing detailed
observation from Earth. 

     Data from the instrument's observations are used for solar physics
studies and for a study of the Sun's influence on Earth's atmosphere.  In
addition, SUSIM will continue to make measurements that coincide with
those from a similar instrument on UARS to help calibrate the satellite
instrument.  During the first 800 days of the UARS mission, the UARS SUSIM
instrument lost 90 percent of its sensitivity to short wavelengths for one
of its channels.  The ATLAS SUSIM data can greatly reduce the UARS error
by providing an estimate of this sensitivity loss. 

     During ATLAS 1, SUSIM collected more than 100 solar ultraviolet
radiation measurements.  On ATLAS 2 , it collected data through 24 orbits
of solar pointing.  Comparisons of data obtained by SUSIM during Spacelab
2, ATLAS 1 and ATLAS 2 show there was a drop in the total amount of
ultraviolet irradiance from the Sun between 1985 and 1993.  Significantly,
observations made during ATLAS 2 did not confirm many of the assumptions
about the way ultraviolet spectral lines would follow Sunspot activity. 
Rather, ultraviolet changes appear to be larger than what would be
predicted by the change in sunspot and total constant change. 

     Located on the ATLAS 3 platform, SUSIM is composed of two precision
ultraviolet spectrometers with two sets of optics and an in- flight
calibration deuterium lamp.  A new internal computer, the Dedicated
Experiment Processor (DEP) and a new version of flight software have been
added to the SUSIM experiment for the ATLAS 3 mission.  Also, several
electronics modules have been modified to allow the processor to collect
more accurate wavelength measurements over the entire spectrum.  These
changes should significantly improve the total accuracy of the data. 

The ATLAS-3 Team

     The ATLAS program is sponsored by NASA's Office of Mission to Planet
Earth in Washington, D.C.  The management and control of each ATLAS
mission is the responsibility of NASA's Marshall Space Flight Center in
Huntsville, Ala.  The mission manager directs a civil service and
contractor team effort to match science objectives with Shuttle-Spacelab
resources so each flight is fine-tuned to gather the maximum amount of
science information.  This effort includes preparing a minute-by-minute
schedule, called a timeline, that combines crew activities, experiment
requirements, Spacelab resources and Shuttle maneuvers into an efficient
operating plan. 

     Principal investigators of the individual experiments form an
Investigator Working Group that meets regularly before the mission to
advise the mission manager's team on science-related issues and payload
operations.  The working group is chaired by the mission scientist, a
member of the mission manager's team. 

     During the mission, the management, principal investigators and
science teams collect scientific data from ATLAS instruments around the
clock from NASA's Spacelab Mission Operations Control facility at
Marshall.  The facility contains banks of computers, monitors and
communication consoles which enable the ground team to monitor the
payload, collect data, send direct commands to the experiments and
communicate with the Shuttle crew.  The SSBUV instrument will also receive
commands from payload operations control centers at Goddard Space Flight
Center. 

     The science team will meet twice daily during the mission as a
Science Operations Planning Group, which includes the investigators for
the CRISTA-SPAS instruments.  The team evaluates science activities, solve
problems and recommend ways to take full advantage of any unplanned
opportunities. 

     Every ATLAS flight crew is divided into two teams, each of which
works a 12-hour shift so science operations can continue around the clock. 
At least one member of each team has special training in both Spacelab and
experiment operations and will oversee science activities on the shift. 
Most of the ATLAS instruments operate automatically, commanded by the
Spacelab computers or by the science teams in Huntsville.  However,
crewmembers can use keyboards to enter observation sequences if necessary. 
Another crewmember on each team is part of the orbiter crew and is
responsible for maneuvering the Shuttle when an instrument requires
precise pointing or must be operated in a specific attitude. 



Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere-
Shuttle Pallet Satellite (CRISTA-SPAS)

     Complementing the ATLAS science mission, the German-built Astronomy
Shuttle Pallet Satellite (ASTRO-SPAS) will carry two instruments to
investigate the Earth's atmosphere.  The ATLAS 3/CRISTA-SPAS mission will
constitute a joint science mission, with a single set of science
objectives managed by a single science team. 

     The ASTRO-SPAS will carry the Cryogenic Infrared Spectrometers and
Telescopes for the Atmosphere (CRISTA) and the Middle Atmosphere High
Resolution Spectrograph Investigation (MAHRSI).  CRISTA will observe a
variety of gases in the middle atmosphere and MAHRSI will measure amounts
of nitric oxide and hydroxyl in the middle atmosphere and lower
thermosphere.  Also onboard the satellite will be the small Surface
Effects Sample Monitor (SESAM), a materials- science experiment aimed at
measuring decay of surfaces exposed to the near-Earth space environment. 

     By operating apart from the Shuttle, CRISTA AND MAHRSI are
independent of orbiter maneuvers.  Since the satellite is deployed and
retrieved on a single flight, data tapes can be retrieved and the
instruments recalibrated in the same way as the ATLAS instruments. 

     The ASTRO-SPAS program is based on a Memorandum of Understanding
between NASA and the German Space Agency (DARA) and makes provisions for
several joint missions.  The first of these missions - ORFEUS-SPAS - was
launched on September 12, 1993, aboard STS-51.  The satellite carried the
German Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph
(ORFEUS) telescope.  CRISTA-SPAS is the second mission in this series. 

The CRISTA-SPAS Mission

     CRISTA-SPAS will be carried to space in the cargo bay of the Shuttle
Atlantis. Early in the mission, the crew will position the satellite using
the Remote Manipulator System.  After release, the CRISTA-SPAS will fly
from 25 to 44 miles (40 to 70 km) behind the Space Shuttle.  The satellite
will operate independently, except for required communication periods with
the Orbiter.  During these periods, the instrument will relay information
about its status through Atlantis to the CRISTA-SPAS station at KSC.  The
first opportunity to communicate with Atlantis will occur immediately
after the release of CRISTA-SPAS.  Additional communication opportunites
will occur every 10 to 12 hours. 

     The payload will be controlled from the German SPAS Payload
Operations Center (SPOC) at KSC.  The orbiter will link CRISTA-SPAS and
the ground station.  After approximately one week, the satellite will be
retrieved and returned to Earth, where the data will be processed and the
instruments will be refurbished. 

INSERT H

     The ASTRO-SPAS carrier is designed for up to 14 days of autonomous
operation in the vicinity of the Space Shuttle orbiter.  It is
approximately 15 feet (4.6 meters) in height, 7 feet (2 meters) in length
and weighs approximately 7,500 pounds (3,400 kilograms).  Precise attitude
control is achieved by a 3-axis stabilized cold gas system incombination
with a star tracker and two specially developed Global Positioning
Satellite (GPS) receivers.  Power is generated by a battery package which
can supply 20 to 50 kilowatt hours to the science instruments depending on
mission requirements.  The spacecraft also carries a central onboard
computer for satellite operation and attitude control which also execute
commands and an S-band transponder for communications with the ground
which is relayed through the Space Shuttle orbiter. 

CRISTA-SPAS Pre-launch Processing

     The versatility of the ASTRO-SPAS as a science platform permits it to
support experiments ranging from ultraviolet astronomy to infrared sensing
of the Earth's atmosphere.  Refurbishment between missions can be achieved
in less than a year. 

     The ASTRO-SPAS payload arrived at NASA Spacecraft Hangar AM on Cape
Canaveral Air Station on June 20 to begin the integration of instruments
and checkout.  It was moved to the Vertical Processing Facility on Sept.
20 for tests to verify compatibility with the Space Shuttle Atlantis. 
Finally, the payload is scheduled to be taken to the launch pad on Oct. 6
for installation into the payload bay of Atlantis on Oct. 11. 

CRISTA-SPAS Instruments

Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere
(CRISTA).  Principal Investigator:  Dr. Dirk Offermann, University of
Wuppertal, Wuppertal, Germany

     The CRISTA instrument will gather the first global information about
medium and small scale disturbances in trace gases of the middle
atmosphere.  These measurements will be taken in three directions
simultaneously and will provide information about disturbances caused by
winds, wave interactions, turbulence and other processes. 

     Evidence suggests there are small three-dimensional wave-shaped
patterns in the middle atmosphere, such as the wave-line variations seen
during balloon flights.  Many other small atmospheric structures have been
predicted theoretically; however, they cannot be measured by current
satellite instruments.  These structures may be of important influence on
many processes in the atmosphere, and precise horizontal and vertical
measurements with good resolution are needed to validate and possibly
improve models of the atmosphere and Earth's energy balance. 

     Instruments previously used to measure the compositions of the middle
atmosphere work in either one direction or two.  For example, instruments
on balloons and rockets take vertical measurements, and most instruments
on satellites provide measurements on a two- directional basis. 
Previously, it has not been possible for scientists to take global
measurements in all three dimensions with good spectral resolution at
once. 

     CRISTA is an infrared instrument composed of three telescopes, with
four spectrometers.  Three of the spectrometers measure near infrared
wavelengths (4 to 13 micrometers), and the fourth is sensitive to the
far-infrared wavelengths (14 to 71 micrometers). Each telescope has a
short-wavelength spectrometer attached, and the center telescope also
holds the spectrometer that measures longer wavelengths. 

     Because of the high speed of CRISTA-SPAS (about five miles, or eight
kilometers, per second) optics and detectors must be very fast to achieve
good resolution for the measurements.  The spectrometers take one spectrum
per second and measure up to 15 gases in 26 channels during this time. 
The telescopes obtain complete altitude observations of these gases within
about one minute as the lines-of-sight are scanned through the atmosphere. 
The required high measurement speed and the required high sensitivity is
achieved by cryogenically cooling the CRISTA optics and detectors. 

     The CRISTA instrument is contained in a vacuum container cooled with
liquid helium.  The container is covered by a motorized door assembly.  An
electronics module that controls and monitors the functions and
measurements of the instrument is contained in a Get- Away Special
canister also located on the ASTRO-SPAS satellite.  The satellite has its
own pointing system and, by operating apart from the Shuttle, is not
affected by orbiter maneuvers.  CRISTA data is stored on the on-board data
recorder. 

The Middle Atmosphere High Resolution Spectrograph Investigation (MAHRSI). 
Principal Investigator:  Dr. Robert Conway, Naval Research Laboratory,
Washington, D.C. 

     MAHRSI will measure amounts of hydroxyl and nitric oxide in the
middle atmosphere and lower thermosphere, from 24 to 72 miles (40 to about
120 km) high.  The experiment also will provide precise knowledge of the
density and temperature in the upper atmosphere. 


     This information will be used to test many theories that havebeen
based on assumed values and will provide the first global vertical
measurements of hydroxyl in the stratosphere. 

     The area of the middle atmosphere between 25 and 75 miles altitude
(40 and 120 km) is too high for balloon experiments, but is too quickly
crossed by sounding rockets for scientists to obtain adequate data. 
Investigators have had to make assumptions regarding the atmospheric
composition found in this region, and they have had to estimate the
effects of vertical and horizontal mixing on its chemistry.  Using horizon
scanning, MAHRSI will measure the ultraviolet sunlight scattered by
hydroxyl and nitric oxide in this region of the atmosphere to give
scientists new information about these important gases. 

     Hydroxyl is an important part of the hydrogen family that contributes
directly to destroying the ozone in the middle atmosphere.  Hydroxyl
combines with molecules of the "odd" nitrogen family to form nitric acid
and other ingredients that participate in ozone chemistry.  At heights
above 37.5 miles (60 km) the distribution of nitric oxide is changed by
winds and currents from the lower thermosphere. 

     MAHRSI also will provide a unique measurement of the temperature of
the atmosphere in the region around 62.5 miles (100 km) high, the coldest
region of the atmosphere.  In a cooperative observation with CRISTA, this
temperature and the nitric oxide quantity information will be combined to
give important understanding of the thermal balance, which plays a
significant role in ozone chemistry. 

     MAHRSI data will help scientists more accurately test the present
understanding of ozone levels in the middle atmosphere and resolve
conflicts between satellite ozone observations and the ozone amounts
predicted by computer models. 

     MAHRSI takes high-resolution ultraviolet measurements of daytime
radiation in Earth's atmosphere, in the wavelength range between 190 and
320 nanometers.  MAHRSI measures light from hydroxyl and nitric oxide
after these molecules absorb ultraviolet energy from the Sun.  Hydroxyl
measurements will be taken between 22 to 56 miles (35 to 90 km), and
nitric oxide measurements from 28 to 90 miles (45 to 145 km). 

     By knowing the shape of the nitric oxide band, researchers can also
determine the temperatures of the atmosphere at heights from 56 to 75
miles (90 to 120 km).  MAHRSI will take either complete nitric oxide
measurements or complete hydroxyl measurements each orbit. 


     MAHRSI consists of a Czerny-Turner spectrograph with a 30-inch
(75-cm) focal length behind a 20-inch (50-cm) focal length telescope
mounted on the ASTRO-SPAS satellite.  MAHRSI transmits information to the
recorder on-board. 

CRISTA-SPAS Management

     DARA is responsible for CRISTA-SPAS mission management, while overall
science management for the joint science mission is the responsibility of
NASA's Marshall Space Flight Center.  Dr. Roland Wattenbach of Deutsche
Agentur Fr Raumfarhtangelegenheiten (DARA), Bonn, Germany, is the
ASTRO-SPAS program manager.  Dr.  Konrad Moritz of Deutsche Aerospace
(DASA) is the CRISTA-SPAS mission manager. 


Detailed Test Objective 835:  Mir Approach Demonstration

     For the retrieval of CRISTA-SPAS on the 10th day of STS-66, Atlantis
will use a new rendezvous approach to the satellite than has been standard
for past satellite retrievals. Rather than approaching forthe final
approximately 1.5 miles to CRISTA-SPAS from a point directly ahead of the
satellite, Atlantis will approach from beneath the satellite. An approach
from directly in front of the satellite is called a V-Bar approach, or
approaching directly along the velocity vector of the satellite. The V-Bar
approach is the standard technique that has been used on all past shuttle
rendezvous. Atlantis will use a different approach, flying the final mile
to CRISTA-SPAS along the R-Bar, an imaginary line drawn from the
satellite to the center of the Earth. 

     The R-Bar approach is being evaluated for use in rendezvous with the
Russian Mir Space Station in 1995 due to the propellant savings that it
may achieve. Approaching the Mir, the shuttle will have to fire its
braking jets in a mode called low Z, where jets facing toward Mir do not
fire and risk damaging the station. Instead, braking of the shuttles
approach is performed by firing jets offset from facing directly at the
station. The low Z approach requires more propellant when used during a
V-Bar rendezvous approach than during an R-Bar approach. To fully evaluate
the planned Mir rendezvous, Atlantis will use low Z braking as it
performs the R-Bar CRISTA-SPAS rendezvous. The new approach may not only
conserve propellant when approaching the Mir station but also could mean
less braking thruster firings are required during the rendezvous in
general, reducing any risk of damaging Mir. 


Experiment of the Sun for Complementing the Atlas Payload and for
Education-II (ESCAPE-II)

     ESCAPE II (Experiment of the Sun for Complementing the Atlas Payload
and for Education), a student-designed and -developed payload, will gather
data that will contribute to a better understanding of the Sun's radiative
effects on the Earth's upper atmosphere. 

     The ESCAPE II experiment was designed, managed and built entirely by
undergraduate and graduate students at the Colorado Space Grant Consortium
at the University of Colorado, Boulder.  The consortium is a group of 13
state colleges and universities, linked by NASA in 1989 as part of a
national effort to help maintain America's preeminence in space. 

     Instruments on ESCAPE II include a spectrometer and a digital imaging
telescope, which will gather data in extreme ultraviolet wavelengths in
which little research has been done over the last 20 years. 

     ESCAPE II will obtain digital images of the solar disk in Lyman
alpha, a wavelength (121.6 nm) in the extreme ultraviolet.  The students
of ESCAPE II project are hoping the images will provide a correlation
between solar activity and solar radiation reaching the Earth's
atmosphere. 

     The ESCAPE II experiment is expected to shed new light on how the
Sun's extreme ultraviolet wavelengths affect the temperature and chemical
composition of the upper atmosphere.  Understanding such
variation is critical changes in solar radiation are known to influence a
wide variety of chemical processes, including the natural production and
destruction of stratospheric ozone.  The release of human-produced
chlorofluorocarbons (CFCs), is believed to be largely responsible for the
recent seasonal decline in stratospheric ozone levels, most markedly over
the Earth's poles.  But to understand the magnitude of human- caused
changes in the atmosphere, scientists first need to measure the
variability of natural solar radiation. 

     The objectives of the ESCAPE II team earned the payload status as a
secondary payload to NASA's ATLAS 3 mission.  NASA's Get Away Special
(GAS) program provided the students with an experiment canister that will
be bolted into the payload bay of the Space Shuttle Atlantis.  It is
roughly 3 feet tall and 23 inches in diameter. ESCAPE II's instruments are
contained in the canister, which has been fitted with a motorized door to
accommodate view of the solar disk. 

     ESCAPE II is a follow-on payload to ESCAPE I (Extreme ultraviolet
Solar Complex Autonomous Payload Experiment), which flew in April 1993
onboard the Space Shuttle Discovery as part of the STS-56/ATLAS 2 mission.  


NATIONAL INSTITUTES OF HEALTH-R-1

     The NIH-R-1 payload is a collaborative developmental biology
experiment developed by NASA and the National Institutes of Health (NIH). 
The 11 experiments that comprise NIH-R-1 will study the effects of space
flight on developing rats.  These experiments will provide important
insights into the fields of gravitational and space biology and gravity's
effects on living organisms. 

     Flying in the Space Shuttle's middeck, the payload consists of two
Animal Enclosure Modules (AEMs), each containing five pregnant rats. 
There are nine U. S. principal investigators, along with a principal
investigator from France and one from Russia. 


Effects of Space Flight on Muscles and Nerves

Kathryn Clark, Ph.D.
University of Michigan
Ann Arbor, Mich.

     The goal of this study is to understand the effects of gravity on the
formation, development and growth of rodent thigh muscles and nerves from
a small, general mass of cells to fully developed systems.  This study
will further our understanding of how muscles develop and may also lead to
advances in treatment of muscles following injury or disease. 


An Experiment to Study the Role of Gravity in the Development of the Optic
Nerve

James L. Lambert, Ph.D.
Jet Propulsion Laboratory
Pasadena, Calif.

     The purpose of this experiment is to identify changes in development
of the optic nerve in rats exposed to the weightlessness of space prior to
birth.  The results of this research may help us begin to understand the
way in which gravity influences the development of our visual system. 

     In young animals, the final route or destination of electrical
impulses from eye to brain is not well defined.  The brain receives "fuzzy
images" of the world because images captured by the eye may be sent to a
range of points in the brains visual center.  The microgravity
environment of space may indirectly play a role in modifying the retina to
brain signal pattern. 


Effects of Weightlessness on Vestibular Development

Bernd Fritzsch, Ph.D.
Creighton University
Omaha, Neb.

     This experiment addresses the questions of whether gravity is
essential for the normal development of balance and whether weightlessness
causes the growth of abnormal connections in brain
areas that control balance. 

     Animals that are in space for even brief periods are unable to
maintain their balance when they return to Earth.  Although adults regain
the ability to orient to gravity within a few days, some animals raised in
space never acquire the ability to orient in gravity. 

     One cause of this abnormal response to gravity may be the development
of the connection between the gravity receptor of the ear and the brain. 
This experiment will study rats that develop in space beginning at an age
before these connections are formed until near the time of birth. 


Effect of Spaceflight on Development of Immune Responses

Gerald Sonnenfeld, Ph.D.
Carolinas Medical Center
Charlotte, N.C.

     Space flight has been shown to change immune responses, which are
those responses of the body that protect people and other animals from
infection.  These changes in immune responses could be due to the very low
gravity found in space, as well as to other factors such as stress. 
Changes in immune responses could have an impact on the body's ability to
resist infection.  The current flight study will look at the effects of
space flight on immune responses of developing rats. 

     The results of this study should indicate whether or not exposure of
a developing rat to space flight will have an effect on its ability to
have a normal immune response.  This should provide information about the
human immune system as well.  In addition, the increased understanding of
the development of immune responses could aid in the development of
treatments for medical problems on Earth.  For example, we may be able to
find new ways to fight diseases in children on Earth. 


Choroid Plexus, Brain and Heart NP Development in Space

Jacqueline Gabrion, Ph.D.
Universit de Montpellier
Montpellier, France

     This experiment, sponsored by CNES (the French Space Agency), will
study the effects of reduced gravity conditions on fluid regulation
systems in the hearts, brains and bodies of rats developing in space. 
This experiment will study how the distribution of fluid regulating
hormones change when the rat develops in microgravity. 

     Studies performed on the heart and brain during ground development
have shown that these systems are different in developing and adult rats. 
This mission offers the first opportunity to obtain basic information on
the effects of microgravity on the generation, storage and release of
these hormones in the heart and brain of developing rats. 


Fluid-Electrolyte Metabolism

Luba Serova, Ph.D.
Institute of Biomedical Problems
Moscow, Russia

    This experiment will examine whether microgravity causes serious
physiological changes in the mother rat, which in turn may induce changes
in fluid electrolytes.  Fluid electrolytes are substances that, in liquid
form, easily transmit electric current; they are often mineral or nutrient
rich.  This experiment will examine whether microgravity causes serious
physiological changes in the mother rat, which in turn may induce changes
in fluid electrolytes, directly affecting signal transmission between
nerves in developing offspring. 

     Previous Russian space flight studies have shown that pregnant rats
exposed to microgravity for five days were able to maintain the
fluid-electrolyte balance of developing rats within their normal limits. 
However, this led to serious changes in the mother rat, including
significantly delayed body weight gain and reduced calcium in the liver
and kidneys. 

     The objective of this flight experiment is to measure water, sodium,
potassium, calcium, magnesium, copper, zinc and iron in developing rats
that will have spent almost half of their gestation period in
microgravity. 

     Other objectives are to measure the size of segments of various areas
of the skeleton, to identify developmental abnormalities in young rats and
to examine the size and tissue structure of different organs of young rats
that have developed in space. 


Microgravity and Placental Development

Randall H. Renegar, Ph.D.
East Carolina University School of Medicine
Greenville, N.C.

     This experiment will use pregnant rats to determine the effect of
microgravity on development of the rat placenta. 

     Ten pregnant rats will be aboard the space shuttle during its 11-day
mission.  Upon return to Earth, the rat uteruses and placentas will be
examined. Hormones produced by these tissues will be analyzed to determine
whether the cells involved have retained their structure and are operating
correctly.  These studies could identify factors that regulate pregnancy
and provide important insights of the role that gravity plays in pregnancy
on Earth . 


Spaceflight Effects on Mammalian Development

Jeffrey Alberts, Ph.D.
Indiana University
Bloomington, Ind.

     The vestibular system, which develops before birth, is the part of
the body and brain that senses and translates information about gravity,
thus providing the basis for balance, movement and coordination. 

     There is reason to expect that the vestibular system needs
gravitational information to establish its early function. But there is no
way to remove gravity on Earth, so the microgravity conditions of space
provide the best insight into the role of gravity in early mammalian
development.  Studying the behavior of rats that have not been exposed to
the normal force of gravity may provide information about the earliest
development of the vestibular system. 


Effect of Gravity on the Attachment of Tendon to Bone

Roger B. Johnson, D.D.S., Ph.D.
University of Mississippi, School of Dentistry
Jackson, Miss.

     The strength of the attachment of tendons to bone is important to the
movement of the legs.  There is little information about the effects of
space flight on the attachment of tendons to bone.  This experiment is
designed to determine if these attachments become weakened during space
flight.  If so, tendons could be torn from the bone, producing a serious
injury and pain, thus preventing normal movement of the legs. 

     This experiment will study the attachment of tendons to the shin bone
and heel of rats following their return from space flight.  The
attachments of the quadriceps and hamstring muscles to the shin bone and
the calf muscle to the heel (the Achilles tendon) will be given special
attention.  This study will provide new and important information
concerning the probability of damage to the attachment of tendon to bone
during space flight and will aid in research designed to prevent such
injuries to astronauts during future space flights. 


Effect of Microgravity on Epidermal Development in the Rat

Steven B. Hoath, M.D.
Childrens Hospital Medical Center
Cincinnati, Ohio

     The effects of space flight and microgravity on the multiple
functions of the skin have not yet been explored.  This research will
examine the composition, organization and integrity of the skin rats
develop under the conditions of space flight.  Analysis will include: the
amount of calcium in the skin; a microscopic look at the cellular
organizationof its outermost layer; and measurement of selected
properties.  The data obtained from these studies will result in a better
understanding ofthe effects of non terrestrial environments in altering
the development and maturation of skin. 


Development of Sensory Receptors in Skeletal Muscle

Mark DeSantis, Ph.D.
University of Idaho
Moscow, Idaho

     This study of rats that undergo part of their prenatal development in
space will examine microscopically the formation of sensory
receptors(known as muscle spindles) and tendon organs in hind limb
skeletal muscles.  It will determine the presence, number and size of the
muscle spindles.  This research also will examine the effects of
microgravity on the hind limb walking patterns of the rats. 



NATIONAL INSTITUTES OF HEALTH-C-2

     The NIH-C-2 payload is comprised of two collaborative biomedical
experiments sponsored by NASA and the National Institutes of Health (NIH). 
These two experiments will make use of a computerized tissue culture
incubator known as the Space Tissue Loss (STL) Culture Module.  STL was
developed at the Walter Reed Army Medical Center in Washington, D.C., to
study cells in microgravity.  Both experiments will study the effects of
space flight on cells from chicken embryos. 



Investigations of the Effects of Microgravity on in vitro
Cartilage 
Calcification

Adele L. Boskey, Ph.D.
Hospital for Special Surgery
New York, N.Y.

     Analyses of the crystals found in the bones of young chickens hatched
from eggs flown in space have shown the presence of smaller crystals
(cartilage or hydroxyapatite crystals) and the absence of any change in
mineral crystal properties compared with Earth-based controls. 

     In this experiment, a scientific model of naturally occurring
cartilage (a cartilage matrix) will be used to simulate animal cartilage. 
The experiment focuses on mineral deposition or calcification of
cartilage.  This experiment will be used to compare the mineral formed in
the microgravity of space with that formed on Earth.  Cultures at two
different stages of development will be fixed for analysis at five points
during the flight, allowing evaluation of changes in proliferation,
maturation and mineralization of the cultures.  Two additional cultures
will be fixed after re-entry. 


     Results will provide direct insight into how calcification in
cartilage and bone may be controlled in space.  This knowledge is
important prior to extended human stays on the Space Station and may also
provide a better understanding of the events involved in normal bone
development on Earth.  Such understanding may eventually lead to the
development of improved treatments for osteoporosis and other bone
disorders. 


Effect of Space Travel on Skeletal Myofibers

Herman H. Vandenburgh 
The Miriam Hospital and Brown University
Providence, R.I.

     This experiment will use tissue-cultured muscle cells to study the
effects of space flight on muscle atrophy, protein turnover rates and
growth factor secretion.  The results of the experiment will indicate
whether tissue cultured skeletal muscle fibers exposed to microgravity
atrophy in the same way as fibers in humans and other animals do on Earth. 
The lack of tension on muscles in space, due to the lack of gravitational
force, offers the opportunity to study the cellular mechanisms that cause
microgravity-induced atrophy. 

     This type of research may help identify and develop countermeasures
to sustain muscle strength on long-duration space voyages.  The experiment
also will provide a rapid screening system for testing drugs to prevent
muscle atrophy on Earth. 



PROTEIN CRYSTAL GROWTH EXPERIMENTS

Dr. Larry DeLucas
University of Alabama in Birmingham
Birmingham, Ala.

     The STS-66 mission will carry two related systems  the Crystal
Observation System, housed in a Thermal Enclosure System (COS/TES), and
the Vapor Diffusion Apparatus, housed in a Single-locker Thermal Enclosure
System (VDA/STES)  to continue research into the structure of proteins
and other macromolecules such as viruses.  In addition to using the
microgravity of space to grow high-quality protein crystals for structural
analysis, the experiments help develop technologies and methods to improve
the protein crystallization process on Earth as well as in space. 

     Proteins are important, complex biochemicals that serve a variety of
purposes in living organisms.  Determining their molecular structure will
lead to a greater understanding of functions in living organisms. 
Knowledge of the structure can also assist the pharmaceutical industry in
the development of disease-fighting drugs. 

     Many proteins can be grown as crystals and their molecular structure
determined through analysis of the crystals by X-ray crystallography. 
Unfortunately, crystals grown in the gravity environment of Earth often
have internal defects that make such analysis difficult or impossible.  As
demonstrated on Space Shuttle missions since 1985, some protein crystals
grown in space -- away from gravity's distortions -- are larger and have
fewer defects. 

     Some of the proteins to be grown on STS-66 are: serum albumin, malic
enzyme, aldehyde reductase and thrombin inhibitor complex. 

     Experiments in both crystal growth systems will evaporate large
droplets of protein solution to begin the crystallization process.  The
protein solution and precipitating agent are carried into space in
opposite sides of a double-barreled syringe. 

     At the beginning of the mission, an astronaut pushes the syringe
pistons to form a drop at the tip of each syringe.  Water evaporates from
the droplet in the growth chamber, and it is transferred as vapor to an
absorbent wicking material in a receiving container.  Proteins in the
droplets crystallize as their concentrations rise.  Crystals can be viewed
through a window in the growth chamber.  At the end of the mission, the
crew retracts the droplets with crystals into the syringes for safe return
to Earth. 

     Small video cameras within the Crystal Observation System will allow
investigators to observe growing protein crystals several times a day,
without excessive crew handling that could disrupt growth and without
removing the system from its temperature-controlled environment.  These
observations could help scientists refine their control of the growing
conditions, which could produce larger crystals with a more uniform
internal order. 

     The Vapor Diffusion Apparatus (VDA) includes three trays, each
containing 20 protein crystal growth chambers.  The crew will turn a
handwheel on each tray at the beginning of the mission to start growth,
and each tray will be scanned with a video camera.  The tray will be
rescanned and photographed at the end of the mission. 

     The experiments are sponsored by NASA's Office of Life and
Microgravity Sciences and Applications. 


SPACE ACCELERATION MEASUREMENT SYSTEM (SAMS)

     The Space Acceleration Measurement System (SAMS) will be flying for
the eleventh time aboard the Space Shuttle.  The middeck payloads that
SAMS is supporting are the Protein Crystal Growth (PCG) experiments.  SAMS
will collect and record data characterizing the microgravity environment
in the Shuttle's middeck. 

     Proteins play an important role in everyday life, from providing
nourishment to fighting disease.  Analyses of crystal forms of proteins
can reveal much about how they work.  Earth-grown crystals that are large
enough to study often have numerous flaws caused by gravity.  The study of
crystals grown in space could lead to the development of foods with higher
protein content and the design of more effective drugs. 

     SAMS will provide the scientists studying these crystals with the
information of the microgravity environment that these crystals
experienced during the mission.  The scientists will be able to account
for the rocket thruster firings, crew activity and background vibrations
that influence these delicate experiments.  The instrument is managed by
NASA's Lewis Research Center, Cleveland, Ohio for the agency's Office of
Life and Microgravity Sciences and Applications, Washington, D.C. 


HEAT PIPE PERFORMANCE AND WORKING FLUID BEHAVIOR IN 
MICROGRAVITY (HPP)

     The Heat Pipe Performance-2 (HPP-2) Experiment will investigate the
thermal performance and fluid dynamics of heat pipes operating with
asymmetric and multiple heating zones under microgravity conditions.  A
Thermal Performance Apparatus (TPA) mounted to middeck seat studs allows
the Orbiter crew members to test individual heat pipes in the crew
compartment during the flight. Thirty-five tests will be performed with
ten different axially grooved aluminum/freon heat pipes. 

     The design of effective spacecraft thermal control systems requires
an understanding of heat pipe fluid dynamics in a microgravity
environment. This behavior cannot be adequately evaluated on Earth because
gravity tends to dominate the capillary forces developed in the wick. In
the microgravity environment, however, surface tension forces within the
apparatus.  For these reasons, flight experiments are critical for
collecting the data necessary for computer model validation. 

     The original Heat Pipe Performance Flight Experiment (HPP-1) was
flown on STS-52 in October, 1992, to investigate and document the
microgravity behavior and performance of several different types of heat
pipes. Data from HPP-1 was used to modify and validate a NASA heat pipe
computer model known as the Groove Analysis Program (GAP). The current
version of GAP models heat pipes with single and uniform heating and
cooling zones. The HPP-2 experiment will test heat pipes with asymmetric
and multiple heating zones, providing data for correlation with new
modifications to the GAP model. The basic difference between the two
experiments is that HPP-1 tested 'ideal case', or simple heat pipes, while
HPP-2 will test more realistic heat pipe designs that mirror the
complexity of actual spacecraft applications. 

      The end product of the HPP-1 and HPP-2 Flight Experiments will be a
GAP model capable of accurately predicting the performance of any type of
axially grooved heat pipe design prior to manufacture, so large costs in
incurred by building and testing prototype heat pipes can be avoided. The
final version of GAP will allow thermal system engineers to be less
conservative in their designs, leading to fewer heat pipes per spacecraft,
thereby achieving significant weight and cost savings. 




STS-66 CREW BIOGRAPHIES

     Donald (Don) R. McMonagle, 42, Lt. Col., USAF, will be the Commander
(CDR) of STS-68. Selected as an astronaut in 1987, McMonagle was born in
Flint, Mi., and will be making his third space flight. 

     McMonagle graduated from Hamady High School, Flint, Mi., in 1970;
received a bachelors in astronautical engineering from the Air Force
Academy in 1974; and received a masters in mechanical engineering
from California State University-Fresno in 1985.

     McMonagle completed pilot training with the Air Force at Columbus Air
Force Base, Miss., in 1975. He graduated from the Air Force Test Pilot
School as the outstanding graduate of his class in 1981 and served as a
test pilot at Edwards Air Force Base from 1982-1985. He attended the Air
Force Command and Staff College at Maxwell Air Force Base, Ala., from
1985-86. With NASA, his first shuttle flight was as a mission specialist
on STS-39 in April 1991, an unclassified mission devoted to studies for
the Strategic Defense Initiative Office. He next flew as pilot of STS-54
in January 1993, a mission that deployed a NASA Tracking and Data Relay
Satellite and performed astronomical studies using the Diffuse X-Ray
Spectrometer. 

     McMonagle has logged more than 343 hours in space and more than 4,200
hours flying time in a variety of jet aircraft. 

     Curtis (Curt) L. Brown, 38, Lt. Col., USAF, will serve as Pilot
(PLT). Selected as an astronaut in 1987, Brown was born in Elizabethtown,
N.C., and will be making his second space flight. 

     Brown graduated from East Bladen High School, Elizabethtown, in 1974
and received a bachelors in electrical engineering from the Air Force
Academy in 1978. 

     Brown completed pilot training with the Air Force in 1979 and was
assigned to fly the A-10 aircraft at Myrtle Beach Air Force Base, S.C., in
1980. He was reassigned as an A-10 instructor pilot at Davis-Monthan Air
Force Base, Az., in 1982. He attended the Air Force Fighter Weapons School
in 1983 and graduated from the Air Force Test Pilot School in 1986 and
later served as a test pilot in the A-10 and F-16 aircraft. 

     Brown's first shuttle flight was as pilot of STS-47 in September
1992, the first Japanese-U.S. cooperative Spacelab mission. Brown has
logged more than 190 hours in space and 3,700 hours flying time in jet
aircraft. 
 
     Dr. Ellen Ochoa, Ph.D., 36, will be Payload Commander and Mission
Specialist 1 (MS1) on STS-66. Selected as an astronaut in January 1990,
Ochoa considers La Mesa, Ca., her hometown and will be making her second
space flight. 

     Ochoa graduated from Grossmont High School in La Mesa in 1975; 
received a bachelors in physics from San Diego State University in 1980;
and received a masters and doctorate in electrical engineering from
Stanford University in 1981 and 1985, respectively. 

     Ochoa joined Sandia National Laboratories in 1985 in a research staff
position and worked on developing optical methods for distortion-invariant
object recognition and optical filters for noise removal, becoming a
co-inventor on two patents in these areas. Her doctoral dissertation on
using photorefractive crystals, a real-time holographic medium, in a
coherent four-wave mixing optical system to perform nonlinear filtering of
images also resulted in a patent. In 1988, Ochoa joined NASA's Ames
Research Center, Moffett Field, Ca., to lead a research group in optical
processing and later as chief of the Intelligent Systems Technology
Branch, performing research and development of high performance
computational systems for aerospace missions. 

     Ochoa's first flight was as a mission specialist on STS-56 in April
1993, the second flight of the Atmospheric Laboratory for Applications and
Sciences (ATLAS-2). Ochoa has logged more than 216 hours in space. 

     Joseph (Joe) R. Tanner, 44, will be Mission Specialist 2 (MS2). 
Selected as an astronaut in 1992, Tanner was born in Danville, Ill., and
will be making his first space flight. 

     Tanner graduated from Danville High School in 1968 and received a
bachelor's in mechanical engineering from the University of Illinois in
1973. 

     Tanner joined the Navy after high school and completed pilot training
in 1975, later serving as an A-7E pilot with Light Attack Squadron 94
aboard the USS Coral Sea. He completed his regular Navy service as an
advanced jet instructor pilot with Training Squadron 4 in Pensacola, Fla.,
although he remained active in the Naval Reserves. 

     Tanner joined NASA's Johnson Space Center in 1984 as an aerospace
engineer and research pilot, serving as an instructor pilot in the Shuttle
Training Aircraft used to train landing techniques for the space shuttle.
He later became deputy chief of the Aircraft Operations Division. Tanner
has logged more than 6,800 hours flying time in military and NASA jet
aircraft. 

     Jean-Francois Clervoy, 35, a European Space Agency (ESA) astronaut,
will be Mission Specialist 3 (MS3). Selected as an astronaut by ESA in
1992, Clervoy considers Toulouse, France, his hometown and will be making
his first space flight. 

     Clervoy received his baccalaureate from College Militaire de Saint
Cyr l'Ecole in 1976; graduated from Ecole Polytechnique, Paris, in 1981;
graduated from Ecole Superieure de l'Aeronautique et de l'Espace,
Toulouse, in 1983; and graduated as a Flight Test Engineer from Ecole du
Personnel Navigant d'Essais et de Reception, Istres, in 1987. 

     Clervoy worked with the Delegation Generale pour L'Armamente of the
French Space Agency (CNES) from 1983 to 1985 on automatic systems and
attitude control systems of various projects, including the SPOT Earth
Observations Satellite, the STAR inter-satellite optical link and the VEGA
comet probe. In 1985, he was selected as a French Space Agency astronaut
and worked as chief test director of the Parabolic Flight Program and also
in the Hermes Crew Office, Toulouse, where he supported efforts in
extravehicular activity, rendezvous and robotic arms. In 1991, Clervoy
completed six weeks of intensive training in Star City, Russia, on the
Soyuz, Mir and EVA systems. In the JSC Astronaut Office, he has supported
development work on remote manipulator system and robotics issues. 

     Scott E. Parazynski, M.D., 33, will be Mission Specialist 4 (MS4).
Selected as an astronaut in 1992, Parazynski considers Palo Alto, Ca., and
Evergreen, Co., his hometowns and will be making his first space flight. 

     Parazynski attended high school first at the Tehran American School,
Iran, and then graduated from the American Community School, Athens,
Greece, in 1979; received a bachelors in biology from Stanford University
in 1983; and received a doctorate in medicine from Stanford Medical School
in 1989. 

     Parazynski was awarded a NASA Graduate Student Fellowship while in
medical school and conducted research on fluid shifts that occur during
human space flight. Additionally, he was involved in the design of several
exercise devices being developed for long-duration space flight.
Parazynski completed his medical internship at the Brigham and Women's
Hospital of Harvard Medical School in 1990 and completed a 22-month
residency in emergency medicine in Denver, Co., prior to his selection as
an astronaut. 


                                 -end STS-66 Press Kit-