STS-56 PRESS KIT


PUBLIC AFFAIRS CONTACTS

NASA Headquarters

Office of Space Flight/Office of Space Systems Development
Mark Hess/Jim Cast/Ed Campion


Office of Space Science and Applications
Paula Cleggett-Haleim/Mike Braukus/Brian Dunbar


Office of Space Communications/Office of Safety & Mission Quality
Dwayne Brown


Office of Advanced Concepts and Technology
Charles Redmond


Office of Aeronautics
Drucella Andersen/Les Dorr


Ames Research Center                            Langley Research Center
Jane Hutchison                                  Catharine Schauer


Dryden Flight Research Facility                 Lewis Research Center
Nancy Lovato                                    Mary Ann Peto


Goddard Space Flight Center                     Marshall Space Flight Center
Randee Exler                                    June Malone


Jet Propulsion Laboratory                       Stennis Space Center
James Wilson                                    Myron Webb


Johnson Space Center                            Wallops Flight Center
James Hartsfield                                Keith Koehler


Kennedy Space Center
George Diller





Department of Defense

Secretary of the Air Force Public Affairs
Maj. Dave Thurston


USAF Space and Missile Systems Center Public Affairs
Betty Ciotti            Dave Hess



CONTENTS

GENERAL BACKGROUND
     General Release
     Media Services Information
     Quick-Look-Facts
     Space Shuttle Abort Modes
     Summary of Major Activities
     Payload and Vehicle Weights

CARGO BAY PAYLOADS & ACTIVITIES
     Atmospheric Laboratory for Applications & Science 2
     Shuttle Pointed Autonomous Research Tool for Astronomy-201
     Solar Ultraviolet Experiment (SUVE)

MIDDECK PAYLOADS
     STS-56 Education Activities
     Hand-held, Earth-oriented, Real-time, Cooperative, User-friendly,
         Location-targeting and Environmental System (HERCULES)
     Radiation Monitoring Experiment-III (RME-III)
     Air Force Maui Optical Station (AMOS)
     Cosmic Radiation Effects and Activation Monitor (CREAM)
     Shuttle Amateur Radio Experiment (SAREX)
     Commercial Materials Dispersion Apparatus ITA Experiment
     Space Tissue Loss (STL)
     Physiological & Anatomical Rodent Experiment (PARE.03)


CREW BIOGRAPHIES & MISSION MANAGEMENT
     STS-56 Crew Biographies
     Mission Management for STS-56
     Previous Shuttle Missions



March 1993

STS-56 MISSION CONTINUES NASA'S MISSION TO PLANET EARTH

     A variety of scientific questions will be addressed when NASA conducts
Shuttle mission STS-56 in late March 1993.  The crew on Space Shuttle Discovery
will gather data on the relationship between sun's energy output and Earth's
middle-atmosphere chemical make-up and how these factors affect the Earth's
ozone level.

     The crew will use the Atmospheric Laboratory for Science and Applications
(ATLAS 2) and Shuttle Backscatter Ultraviolet (SSBUV) payloads aboard Discovery
to gather this information.

     The source of solar wind and the possible applications a microgravity
environment can provide for research in drug development and the changes which
occur in muscles and bones in a weightless condition are some of the other
areas to be investigated during the STS-56 mission.

     The STS-56 crew will be commanded by Kenneth D. Cameron who will be making
his second Shuttle flight.  Stephen S. Oswald will serve as Pilot and will be
making his second flight.  Rounding out the ATLAS 2 crew will be three mission
specialists - Michael Foale, making his second space flight and Kenneth D.
Cockrell and Ellen Ochoa who will be making their first flight.

     Launch of Discovery is currently targeted for late March from Kennedy
Space Center's (KSC) Launch Complex 39-B.  After launch, the STS- 56 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 8 days and conclude with a landing at KSC's
Shuttle Landing Facility.

     ATLAS 2 is the primary payload for the STS-56 mission, the second in a
series of missions which will track subtle, year-to-year variations in solar
activity and in atmospheric composition.  The ATLAS series is a vital part of
NASA's "Mission to Planet Earth," a long-term effort to study the Earth as a
global environmental system.  The SSBUV experiment which is co- manifested with
ATLAS 2, provides calibrated ozone data contributing to the Mission to Planet
Earth data set.

     The Space Shuttle is the 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 as necessary for scheduled observations.

     The Shuttle's generous payload capacity and power supply allow a diverse
assembly of large instruments to make simultaneous remote observations.  The
Shuttle-borne ATLAS 2/SSBUV instruments make more detailed measurements than
similar instruments now flying aboard satellites.  France, Belgium and Germany
are providing three of the ATLAS 2 instruments.

     Also flying in Discovery's payload bay will be the Spartan-201, a free-
flying payload to study the velocity and acceleration of the solar wind and to
observe aspects of the sun's corona.  Results should help scientists understand
the physics of the sun's corona and the solar wind.  When the Shuttle's payload
bay doors are open, a crew member will use the Remote Manipulator System (RMS)
to lift the Spartan from its rack and release it over the side of the Shuttle.

     Spartan is deployed from the Shuttle so that Spartan can operate
independently, turning and pointing at the sun, while leaving the orbiter free
for other activities.  After completing its observations, Spartan- 201 will be
retrieved using the RMS and will be stowed back in the cargo bay to be returned
to Earth.

     NASA's long standing educational outreach efforts will be highlighted in
two STS-56 experiments - the Solar Ultraviolet Experiment (SUVE) and the
Shuttle Amateur Radio Experiment (SAREX).

     SUVE will be carried in a Get-Away-Special (GAS) canister in Discovery's
cargo bay.  The SUVE experiment will study the extreme ultraviolet solar
radiation as it affects the Earth's ionosphere.  SUVE was developed by students
at the Colorado Space Grant Consortium, a group of 14 colleges and universities
with funding from NASA. NASA's GAS program provides low- cost access to space
for high school and college students as well as other small research groups.

     The Shuttle Amateur Radio Experiment-II (SAREX-II) provides public
participation in the space program, supports educational initiatives and
demonstrates the effectiveness of making contact between the Space Shuttle and
low-cost amateur "ham" radio stations on the ground.  On STS- 56, crew members
Ken Cameron, Ken Cockrell, Mike Foale and Ellen Ochoa will use SAREX-II as a
secondary payload.  Operating times for school contacts are planned into the
crew's activities.  The school contacts generate interest in science as
students talk directly with the astronauts.

     Several experiments, previously flown on Shuttle missions, are aboard
Discovery on the STS-56 mission.

     The Hand-held, Earth-oriented, Real-time, Cooperative, User- friendly,
Location-targeting and Environmental System (HERCULES) experiment, which flew
on STS-53 in December 1992, again will test a system developed to allow a
Shuttle astronaut in space to point a camera at an interesting feature on
Earth, record the image and determine the latitude and longitude of the
feature.

     The Air Force Maui Optical Station (AMOS) experiment, which has been a
part of numerous Shuttle missions, will fly on the STS-56 mission.  The AMOS is
an electro-optical facility located on the Hawaiian island of Maui. The
facility tracks the orbiter as it flies over the area and records signatures
from thruster firings, water dumps or the phenomenon of "shuttle glow."

     Two other experiments which have flown before, Space Tissue Loss-3 and
Physiological and Anatomical Rodent Experiment (PARE.03) will use different
methods to address the issue -- why bones and muscles change when they
experience a weightless condition.

     The Radiation Monitoring Equipment-III (RME-III), flown on several
missions, and the Cosmic Radiation Effects and Activation Monitor (CREAM),
which last flew on STS-44 in November 1991, will be a part of the STS-56
mission.  RME-III is an instrument which measures the exposure to ionizing
radiation on the Space Shuttle. It displays the dose rate and total accumulated
radiation dose to the astronaut operator.  The CREAM experiment is designed to
collect data on cosmic ray energy loss spectra, neutron fluxes and induced
radioactivity.  The data will be collected by active and passive monitors
placed at specific locations throughout the orbiter's cabin.

     The STS-56 mission will be the 16th flight of Space Shuttle Discovery and
the 55th flight of the Space Shuttle.


- end -

MEDIA SERVICES

NASA Select Television Transmission

        NASA Select television is available on Satcom F-2R, Transponder 13,
located at 72 degrees west longitude; frequency 3960.0 MHz, audio 6.8 MHz.

        The schedule for television transmissions from the orbiter and for the
mission briefings will be available during the mission at Kennedy Space Center,
Fla; Marshall Space Flight Center, Huntsville, Ala.; Ames- Dryden Flight
Research Facility, Edwards, Calif.; Johnson Space Center, Houston and NASA
Headquarters, Washington, D.C. The television schedule will be updated to
reflect changes dictated by mission operations.

        Television schedules also may be obtained by calling COMSTOR
713/483-5817.  COMSTOR is a computer data base service requiring the use of a
telephone modem.  A voice update of the television schedule is updated daily at
noon EST.

Status Reports

        Status reports on countdown and launch, on-orbit activities and landing
operations will be produced by the appropriate NASA newscenter.

Briefings

        A mission press briefing schedule will be issued prior to launch.
During the mission, mission status briefings by a flight director or mission
operations representative and representatives from the science team will occur
at least once per day.  The updated NASA Select television schedule will
indicate when mission briefings are planned.



STS-56 QUICK LOOK

Launch Date/Site:       Late March,1993/Kennedy Space Center - Pad 39B
Launch Time:            12:50 a.m. EST
Orbiter:                Discovery (OV-103) - 16th Flight
Orbit/Inclination:      160 nautical miles/57 degrees
Mission Duration:       8 days, 6 hours, 6 minutes
Landing Time/Date:      TBD
Primary Landing Site:   Kennedy Space Center, Fla.
Abort Landing Sites:    Return to Launch Site - KSC, Fla.
                        TransAtlantic Abort landing - Zaragoza, Spain
                                                      Ben Guerir, Morroco
                                                      Moron, Spain
                        Abort Once Around - White Sands, N.M.

Crew:                   Kenneth D. Cameron, Commander (CDR)
                        Stephen S. Oswald, Pilot (PLT)
                        Michael C. Foale, Mission Specialist 1 (MS1)
                        Kenneth D. Cockrell, Mission Specialist 2 (MS2)
                        Ellen Ochoa., Mission Specialist 3 (MS3)

Blue Team:              Cameron, Oswald, Ochoa

Red Team:               Cockrell, Foale


Cargo Bay Payloads:

        ATLAS 2 (Atmospheric Lab for Applications and Science-2)
        SSBUV-A (Shuttle Solar Backscatter Ultraviolet-A)
        SPARTAN-201 (Solar Wind Generation Experiment)
        SUVE (Solar Ultraviolet Experiment)

In-cabin Payloads:

        CMIX (Commercial Materials Dispersion Apparatus)
        PARE (Physiological and Anatomical Rodent Experiment)
        HERCULES (Hand-held, Earth-oriented, Real-time, Cooperative,
                User-friendly, Location-targeting and Environmental System)
        SAREX-II (Shuttle Amateur Radio Experiment-II)
        STL (Space Tissue Loss)
        AMOS (Air Force Maui Optical System)
        CREAM (Cosmic Ray Effects and Activation Monitor)
        RME-III (Radiation Monitoring Equipment-III)


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.

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

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

     STS-56 contingency landing sites are the Kennedy Space Center, White Sands
Space Harbor, Zaragoza, Ben Guerir and Moron.



STS-56 SUMMARY TIMELINE

Blue/Red - Flight Day One
Ascent
OMS-2
Remote Manipulator System checkout
Remote Manipulator System payload bay survey
Shuttle Amateur Radio Experiment set-up
HERCULES set-up
RME activation
Shuttle Solar Backscatter Ultraviolet activation

Red - Flight Day Two
Atmospheric Laboratory for Applications and Science activation
Commercial Materials Dispersion activation
Solar Ultraviolet Experiment activation

Blue - Flight Day Two
ATLAS 2 operations
SUVE operations

Red - Flight Day Three
ATLAS 2 operations
SUVE operations
Laser range finder checkout
HERCULES operations

Blue - Flight Day Three
ATLAS 2 operations
SUVE operations

Red - Flight Day Four
ATLAS 2 operations
SUVE operations
SPARTAN-201 checkout

Blue - Flight Day Four
SPARTAN-201 deploy
Separation burns
ATLAS 2 operations

Red Flight Day Five
ATLAS 2 operations
SUVE operations

Blue Flight Day Five
SPARTAN-201 stationkeeping
ATLAS 2 operations
SUVE operations


Red - Flight Day Six
ATLAS 2 operations
SUVE operations

Blue - Flight Day Six
SPARTAN-201 rendezvous
SPARTAN-201 grapple
SPARTAN-201 berth

Red - Flight Day Seven
ATLAS 2 operations
SUVE operations

Blue - Flight Day Seven
Flight Control Systems checkout
ATLAS 2 operations
SUVE operations

Red - Flight Day Eight
Orbital Debris Radar Calibration System deploy
ATLAS 2 operations
HERCULES operations

Blue - Flight Day Eight
ATLAS 2 operations
SUVE operations
RMS power down and berth
RME deactivation
SAREX deactivation

Red/Blue - Flight Day Nine
ATLAS 2 deactivation
SSBUV deactivation
SUVE deactivation
Cabin stow
Deorbit preparations
Deorbit burn
Landing



STS-56 VEHICLE AND PAYLOAD WEIGHTS

Vehicle/Payload                                 Pounds

Orbiter (Discovery) empty and 3 SSMEs           173,227

ATLAS 2                                         8,360

SPARTAN-201 (deployable)                        2,842

SPARTAN-201 (support equipment)                 2,425

SSBUV                                           733

SUVE                                            593

CMIX                                            71

PARE                                            170

SAREX-II                                        67

RME-III                                         7

CREAM                                           37

HERCULES                                        126

STL                                             58

Total Vehicle at SRB Ignition                   4,500,837

Orbiter Landing Weight                          206,532


ATLAS 2

     ATLAS 2, the second in NASA's series of Atmospheric Laboratory for
Applications and Science Spacelab missions, is the primary payload for the
STS-56 flight.  The Space Shuttle-borne remote sensing laboratory studies the
sun's energy output and Earth's middle-atmosphere chemical makeup, and how
these factors affect levels of ozone, which prevents much of the sun's harmful
ultraviolet radiation from reaching the Earth's surface.

     Ozone depletion has been a serious environmental concern since the 1970s.
In the mid-1980s, British scientists observed significant ozone depletion of
the Antarctic. Visual images of the concentrated, well- defined areas of
depletion gave rise to the term "ozone hole," which has appeared over the
Antarctic since at least 1979.  Satellite observations since then have shown
long-term ozone depletion occurring in the Southern and Northern Hemispheres.

     Concerns over the possible effects of ozone depletion, increases in
cataracts and skin cancer and possible damage to food crops, led to an
international treaty to phase out the use of ozone-depleting chemicals.
However, many questions about the exact mechanisms of ozone depletion remain
unanswered.  To help answer those questions, the ATLAS missions will gather
data on atmospheric chemistry and on the sun's energy - key ingredients in the
ozone cycle.

     Ozone is created and destroyed by complex reactions involving ultraviolet
radiation from the sun and gases in the middle atmosphere, between 10 and 50
miles (15 and 80 kilometers) above the Earth's surface.  ATLAS 1, which flew in
March 1992, established a voluminous baseline of atmospheric and solar data
against which to measure future global change.

     ATLAS 2 and subsequent missions will track subtle, year-to-year variations
in solar activity and in atmospheric composition.  ATLAS instruments are
precisely calibrated before and after flight, so they also provide a valuable
cross-check for data being gathered on a continuous basis by similar
instruments aboard free-flying satellites.

     The ATLAS series is a vital part of NASA's "Mission to Planet Earth," a
long-term effort to study the Earth as a global environmental system.  Mission
to Planet Earth will observe and monitor the interaction of large environmental
components (land, oceans/water/ice, atmosphere and the biosphere).  Data
gathered will be distributed to global change researchers worldwide, allowing
them to better understand natural changes in the Earth and to differentiate
natural change from human-induced change.  Mission to Planet Earth research
will help humans make informed decisions about protecting their environment.

     Scientists from six nations are participating directly in the ATLAS 2
mission, underscoring the worldwide importance of atmospheric and solar
research.  In addition to the United States, investigators represent Belgium,
Germany, France, The Netherlands and Switzerland. ATLAS 2 Instruments

     The Space Shuttle Discovery will carry the ATLAS 2 Spacelab into orbit for
8 days of remote sensing experiments.  Six instruments are mounted in the
orbiter's payload bay on a Spacelab pallet.  The seventh is mounted in two
canisters on the walls of the payload bay.

     The open, U-shaped pallet is reusable Spacelab equipment provided by the
European Space Agency in 1981 as its contribution to the Space Shuttle program.
The instruments' power supply, command and data- handling system and
temperature control system are housed in a pressurized container called an
igloo (also standard Spacelab equipment) located in front of the pallet.  These
seven instruments form the core ATLAS payload which will fly aboard ATLAS 2 as
well as ATLAS 3 scheduled for late 1994.

Atmospheric Science

     % The Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment
identifies the distribution, by altitude, of 30 to 40 different gases between 6
and 85 miles (10 and 140 kilometers) above the Earth's surface.

     % The Millimeter Wave Atmospheric Sounder (MAS) measures water vapor,
ozone and chlorine monoxide (a key compound that contributes to ozone loss), as
well as temperature and pressure in the middle atmosphere.

     % The Shuttle Solar Backscatter Ultraviolet (SSBUV) spectrometer, mounted
on the walls of the payload bay, measures ozone concentrations by comparing
solar ultraviolet radiation with that scattered back from the Earth's
atmosphere.

Solar Science

     % The Solar Spectrum Measurement (SOLSPEC) instrument studies the
distribution of solar energy by wavelength, from infrared through ultraviolet.

     % The Solar Ultraviolet Irradiance Monitor (SUSIM) concentrates on the
sun's ultraviolet radiation, which undergoes wider variations than other
wavelengths.

     % The Active Cavity Radiometer (ACR) and the Solar Constant (SOLCON)
experiments each make extremely precise, independent measurements of the total
energy Earth receives from the sun.

     The steep, 57-degree Shuttle's orbit inclination will take it over points
as far north as Juneau, Alaska, and as far south as Tierra del Fuego, Argentina
-- allowing readings to be made over virtually the entire globe.

     On ATLAS 2, the Atmospheric Trace Molecule Spectroscopy experiment, which
made most of its measurements in the Southern Hemisphere during ATLAS 1, will
focus on the Northern Hemisphere. To view orbital "sunrises" at high latitudes,
a night launch is required.


ATLAS Missions and the Shuttle

     The Space Shuttle is the 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 as necessary for scheduled observations.  The Shuttle's
generous payload capacity and power supply allow a diverse assembly of large
instruments to make simultaneous remote observations.  The Shuttle-borne ATLAS
instruments make more detailed measurements than similar instruments now flying
aboard satellites.

     Because the Shuttle returns the laboratory to Earth after each flight, it
also has the advantage of assured calibration.  ATLAS instruments are
calibrated to a high level of accuracy prior to launch and shortly after the
Shuttle lands, they are recalibrated to ensure their sensitive measurements
remain accurate.

     ATLAS missions take a "snapshot" of the atmosphere for about a week at a
time.  However, atmospheric and solar measurements are being made continuously
by instruments aboard free-flying satellites, such as the Upper Atmosphere
Research Satellite launched in September 1991 and various National Oceanic and
Atmospheric Administration (NOAA) satellites.

     Extended exposure to the harsh environment of space, especially to
ultraviolet radiation, can degrade the accuracy of those instruments.  By
comparing data from the ATLAS instruments to their sister experiments aboard
the free-flyers, scientists can correct for drift in the satellite instruments
and have a high level of confidence in the accuracy of their measurements.

Science Operations Plan

     The ATLAS 2 science operations plan calls for periods of atmospheric data
gathering interspersed with orbits dedicated to solar observations.

     During their designated orbits, the instruments investigating middle
atmospheric phenomena will operate almost continuously.  ATMOS will take solar
radiation absorption readings during each orbital sunrise and sunset. (An
orbital "day," with a sunrise and sunset, occurs approximately every 90 minutes
during flight.)

     MAS will measure microwave emissions from Earth's limb throughout each
orbit, and SSBUV will make its measurements of backscattered ultraviolet
radiation in the daylight portion of these orbits.  The ATMOS and MAS
instruments will be inactive during solar observation periods.

     Solar observations are scheduled early in the flight, on two occasions in
the middle of the mission and during the last full day of science operations.
At these times, ACRIM and SOLCON will measure total solar irradiance.  SUSIM
and SOLSPEC will make solar spectral measurements, and SSBUV will gather its
data on solar ultraviolet radiation.  The Shuttle orbit allows numerous
correlative measurements with UARS and the NOAA satellites.  Similar
instruments aboard these spacecraft will make independent measurements of the
same regions of the atmosphere at about the same time.  Data gathered during
these opportunities will be compared to check the accuracy of readings by the
satellite instruments.

     The ATLAS experiments will gather data from about 4 hours after launch
until approximately 12 hours before landing.  ATLAS operations will be
suspended temporarily during deployment and retrieval of the Shuttle Pointed
Autonomous Research Tool for Astronomy (SPARTAN) free flyer, since Shuttle
maneuvers required for those activities will prevent proper pointing of the
ATLAS instruments.

The ATLAS 2 Team

     The ATLAS program is sponsored by NASA's Office of Space Science and
Applications and is directed by the Earth Science and Applications Division and
the Flight Systems Division, located in Washington, D.C.

     The mission management and control of each ATLAS flight is the
responsibility of NASA's Marshall Space Flight Center, 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 and science teams control the ATLAS
instruments around the clock from NASA's Spacelab Mission Operations Control
facility at the Marshall center.  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.  During the mission the science teams meet twice daily
as a Science Operations Planning Group to evaluate science activities, solve
problems and recommend ways to take full advantage of any unplanned
opportunities.

     The two European solar experiments, SOLCON and SOLSPEC, will be jointly
operated from the NASA control center in Huntsville and from a control center
at the Institut Royal Meteorologique de Belgique, Brussels, Belgium, during
portions of the ATLAS 2 mission.



     Most of the ATLAS instruments operate automatically, commanded by the
Spacelab computers or by the science teams in Huntsville. However, crew members
can use keyboards to enter observation sequences or commands if necessary.
Another crew member 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.


SHUTTLE POINT AUTONOMOUS RESEARCH TOOL FOR ASTRONOMY-201 (SPARTAN-201)

     Spartan-201 is a free-flying payload that will study the velocity and
acceleration of the solar wind and observe aspects of the sun's corona.
Results will help scientists understand the physics of the sun's corona and the
solar wind.

     Spartan is deployed by the Shuttle and retrieved on the same mission.
While overboard it is completely autonomous, providing its own battery power,
pointing system and data recorder as it executes a pre- programmed science
mission.  The Spartan carrier can support a variety of scientific studies and
serve as a test bed for technology development.

     The Space Shuttle offers easy access to a variety of systems that can
conduct scientific investigations from above the Earth's atmosphere.  Spartan
is one of those systems, providing a capability between small attached payloads
and the large, long duration, free-flying satellites.

     Spartan has evolved using sounding rocket class instruments to perform the
scientific studies.  This system provides a significant increase in observing
time compared to sounding rockets.  The simple and efficient Spartan carriers
are reusable and can accommodate a variety of scientific instruments for a
relatively low cost-per-flight.

Spartan-201 Science

     Spartan-201 will look for evidence to explain how the solar wind is
generated by the sun.  Electrons, heavy protons and heavy ions are constantly
ejected from the outer layers of the solar atmosphere.  The Earth encounters
this material continually as it orbits the sun.  The solar wind fills
interplanetary space and sweeps by the Earth at almost 1 million miles per hour
(400 km/sec).  It often blows in gusts and frequently disrupts navigation,
communications and electric power distribution systems on Earth.

     The solar wind originates in the corona, the outermost atmosphere of the
sun.  Two telescopes for studying the corona comprise the science payload of
Spartan 201.  One telescope, the White Light Coronagraph (WLC), will measure
the density distribution of electrons making up the corona.  The other
telescope, the Ultraviolet Coronal Spectrometer (UVCS), will investigate the
temperatures and distributions of protons and hydrogen atoms through the same
layers of the corona.  Ultraviolet radiation, which is absorbed by the Earth's
atmosphere, cannot be observed from the ground.

     A comparison of the white light and ultraviolet data sets will, for the
first time, allow scientists to measure the electron and proton temperatures
and densities in the solar corona This also will yield new evidence on large
flows of material in the corona and allow scientists to test specific theories
on how the corona is heated to its million-degree temperature.

     The UVCS was built by scientists from the Smithsonian Astrophysical
Observatory, Harvard University, Cambridge, Mass. The WLC was developed by the
High Altitude Observatory of the National Center for Atmospheric Research in
Boulder, Colo., and has been transferred to NASA's Goddard Space Flight Center
(GSFC), Greenbelt, Md.

Deployment

     The dual-telescope payload is mounted on the Spartan carrier.  On orbit, a
crew member will use the Remote Manipulator System to lift the Spartan from its
rack and release it over the side of the Shuttle. Spartan will operate
independently, turning and pointing at the sun, leaving the orbiter free for
other activities.  Additionally, by maintaining its distance from the Shuttle,
the Spartan is able to stay clear of any contamination which might be generated
by Shuttle thruster firings.

     Spartan-201 will be deployed on the third day of STS-56. Discovery will
perform a series of engine firings that will put Discovery at a point about 20
nautical miles (37 km) behind the satellite.

     For between 6 and 40 hours, Spartan-201's instruments will observe the
sun.  At about 4 hours prior to the scheduled retrieval time, Discovery will
close on Spartan-201, eventually passing directly below it before Commander
Steve Oswald manually flies Discovery the final few hundred feet to allow the
satellite to be grasped by the robot arm.  Once caught by the arm, Spartan-201
will be stowed back in the cargo bay to be returned to Earth.

     Spartan is designed to be self-operating as much as possible, and the crew
will have no interaction with the satellite other than releasing it and
recapturing it.

History

     The Spartan Program was conceived in the mid-1970s and developed by GSFC
and the U.S. Naval Research Laboratory to extend the capabilities of sounding
rocket class science experiments by making use of the Space Shuttle.

     The telescopes on Spartan-201 have flown previously on sounding rockets.
In June 1985, a Spartan mission carried an x-ray telescope.  Another mission,
Spartan Halley, was on board STS-51L and was destroyed in the Challenger
accident.

     The Spartan program is managed by GSFC for the Office of Space Science and
Applications, Washington, D.C. The Spartan Project Manager is Frank Collins and
the Mission Manager is Jack Pownell, both of Goddard's Special Payloads
Division. The Principal Investigator is Dick Fisher, also of GSFC.


SOLAR ULTRAVIOLET EXPERIMENT (SUVE)

     SUVE is a Colorado Space Grant Consortium project that will study the
extreme ultraviolet solar radiation as it affects the Earth's ionosphere.  The
payload is housed in a single Get-Away Special (GAS) canister, developed by
NASA's Goddard Space Flight Center to provide low-cost access to space for high
school and college students as well as other small research groups.

     The SUVE payload is designed, managed and built entirely by students at
the University of Colorado. Graduate and undergraduate students from aerospace,
mechanical and electrical engineering as well as physics and other scientific
disciplines have been involved since the project's inception.  From project
management to detailed performance analyses, the SUVE project is entirely
student run.

     The Colorado Space Grant Consortium is a group of 14 Colorado colleges and
universities funded by NASA for the express purpose of educating students in
the science and engineering aspects of exploring and working in outer space.
The programs range from introductory education for K-12 students, to design and
development of actual space projects for undergraduate and graduate students.


STS-56 EDUCATION ACTIVITIES

Atmospheric Detectives, ATLAS 2 Teacher's Guide

     A teacher's guide entitled, Atmospheric Detectives, has been developed for
use with middle school students to complement and teach the science objectives
of the ATLAS 2 mission.

     Atmospheric Detectives blends lessons in mathematics, chemistry, physics
and Earth sciences with problem solving exercises in an attempt to nurture
students' natural curiosity and excitement about science and technology.  The
ATLAS 2 teacher's guide probes the connection between the activities of
scientists and researchers and the observable world of weather and climate.

     Students briefly will examine the findings of the ATLAS-1 flight linking
that mission with the science goals of ATLAS 2 and future flights.  As
scientists, students will explore how solar and atmospheric changes might
affect climate, specifically looking at solar output, wind patterns and water
vapor.

     Students will explore how ATLAS 2 investigators measure the effects on
climate using remote-sensing techniques of spectrometry and limb sounding as
well as ground truth studies and exercises emphasizing the importance of
mathematics and precise measurement.

HAND-HELD, EARTH-ORIENTED, REAL-TIME, COOPERATIVE, USER- FRIENDLY,
LOCATION-TARGETING AND ENVIRONMENTAL SYSTEM (HERCULES)
  Naval Research Laboratory (NRL) scientists will again test a system developed
     to allow a Shuttle astronaut in space to point a camera at an interesting
     feature on Earth, record the image and determine the latitude and
     longitude of the feature.

     Called HERCULES, the system includes a modified Nikon camera and a
geolocation device which determines in real-time the latitude and longitude of
Earth images.

     HERCULES will provide a valuable Earth observation system for military,
environmental, oceanographic and meteorological applications.  HERCULES, flown
once before in December 1992 on Space Shuttle flight STS-53, is being
integrated and flown on the Space Shuttle under the direction of the Department
of Defense's Space Test Program.

    Images and geolocation data taken during the STS-53 mission still are being
analyzed, but geolocation accuracies are about 3 nautical miles.  An additional
system feature that will be used during STS-56 is the ability to transmit
images and geolocation data to the Mission Control Center for analysis while
the mission is in progress.

     The project is a joint Navy, Army, NASA effort.  Scientists at NRL's Naval
Center for Space Technology developed the HERCULES Attitude Processor (HAP) and
the alignment, geolocation and human interface software to perform the
geolocation.  The other components in the system are a NASA- built Electronic
Still Camera (ESC) that stores images in a digital form and a modified Nikon
F-4 and Honeywell ring-laser gyro.

     On board the Shuttle, the astronaut will start up the system by pointing
the camera, with the attached gyro, at two known stars to obtain a bearing.
The astronaut then "shoots" images by pointing the camera at the Earth and
snapping the shutter.

     The camera communicates with HAP, which processes the data from the gyro
and determines its absolute orientation in space.  Then, the HAP passes this
pointing information to the NRL software running on a NASA- modified GRID
portable computer.  The computer then determines the longitude and latitude of
the image.

     The geolocation information is sent back to the camera by the HAP, where
it is appended to the image data.  The astronaut can view the image on the
Shuttle and downlink it to Earth. The image and geolocation data are also
stored in the ESC system for post-mission analysis."


     The system is a significant improvement over its predecessor called L-
cubed.  Under the L-cubed system, the astronauts had to take multiple images of
the same target while simultaneously keeping the edge of the Earth in view,
which limited image magnification.

     With HERCULES, the astronaut only needs to look at the point of interest,
allowing the use of many different camera lenses.  In the daytime, the system
uses any Nikon-compatible lens.  At night, it operates with an image
intensifier developed by the Army's Night Vision Laboratory. At any
magnification, images with no distinguishing demographical features can be
captured and geolocated.  HERCULES captures images digitally, which allows
computer analysis and data dissemination, an improvement over the film-based
L-cubed system.

     NRL scientists already are exploring enhancements to HERCULES.
Incorporating Global Positioning System (GPS) hardware into HERCULES would
provide a geolocation accuracy better than 1 nautical mile, and adding a gimbal
system would allow the system to automatically track points on Earth. One
modification to HERCULES being considered is providing orbiter power to the ESC
components rather than using the battery packs utilized on STS-53. By not
having to replace the battery packs, the astronaut will have more opportunities
to test the system.


RADIATION MONITORING EQUIPMENT-III (RME-III)

     The RME-III instrument measures the exposure of ionizing radiation on the
Space Shuttle. RME-III displays the dose rate and total accumulated radiation
dose to the astronaut operator.  Simultaneously RME-III registers the number of
radiation interactions and dose accumulated at 10 second intervals and stores
the data in an internal memory for follow-up analysis upon return to Earth.

    The radiation detector used in RME-III is a spatial ionization chamber
called a tissue equivalent proportional counter (TEPC).  It effectively
simulates a target size of a few microns of tissue, the dimensions of a typical
human cell.  For this reason, TEPC-based instruments such as the RME-III are
called micro-dosimeter instruments.

     RME stands for Radiation Monitoring Equipment, the name given to prototype
dosimeter instruments flown on the Space Shuttle prior to 1986.  The RME-III
has successfully flown on 13 Space Shuttle missions since STS- 26.

     RME is being integrated and flown on this mission under the direction of
the Defense Department's Space Test Program. It has been flown in conjunction
with other radiation experiments, such as the Cosmic Radiation Effects and
Activation Monitor and Shuttle Activation Monitor. It is anticipated that RME
will be flown on several future Space Shuttle missions.



     The data obtained from RME-III is archived and is being used to update and
refine models of the space radiation environment in low Earth orbit.  This will
assist space mission planners to more accurately assess risk and safety factors
in future long-term space missions, such as Space Station Freedom.

    Next generation instruments similar to the RME-III will be flown on Space
Station Freedom and on future manned and unmanned missions to the Moon, Mars
and beyond.  RME-III also is being used to measure radiation exposure in high
altitude aircraft, such as the Concorde.


COSMIC RADIATION EFFECTS AND ACTIVATION MONITOR (CREAM)

     The Cosmic Radiation Effects and Activation Monitor (CREAM) experiment on
STS-56 is designed to collect data on cosmic ray energy loss spectra, neutron
fluxes and induced radioactivity.  The data will be collected by active and
passive monitors placed at specific locations throughout the orbiter's cabin.

     The active monitor will obtain real-time spectral data while the passive
monitors will obtain data during the entire mission to be analyzed after the
flight.  The flight hardware contains the active cosmic ray monitor, a passive
sodium iodide detector and up to five passive detector packages.  All hardware
fits in one locker on Discovery's middeck.

     Once in orbit, a crew member will be available at regular intervals to
monitor the payload/experiment.  CREAM is a Department of Defense experiment
and is flown under the direction of DoD's Space Test Program.


AIR FORCE MAUI OPTICAL SITE (AMOS)

     The AMOS is an electro-optical facility located on the Hawaiian island of
Maui. The facility tracks the orbiter as it flies over the area and records
signatures from thruster firings, water dumps or the phenomenon of "shuttle
glow."

     The Shuttle glow phenomenon around the orbiter is a well- documented
glowing effect caused by the interaction of atomic oxygen with the spacecraft.
The information obtained is used to calibrate the infrared and optical sensors
at the facility.  No hardware onboard the Shuttle is needed for this
experiment.


SHUTTLE AMATEUR RADIO EXPERIMENT-II

     The Shuttle Amateur Radio Experiment-II (SAREX-II) provides public
participation in the space program, supports educational initiatives and
demonstrates the effectiveness of making contact between the Space Shuttle and
amateur "ham" radio stations on the ground.

     SAREX-II was last flown aboard STS-55 and during that flight, there were
dozens of voice contacts with ham stations at schools around the world and
hundreds of contacts with individual ham operators.  On STS-56, crew members
Ken Cameron, call sign N5AWP, Ken Cockrell, call sign KB5UAH, Mike Foale, call
sign KB5UAC, and Ellen Ochoa, call sign KB5TZZ, will use SAREX-II as a
secondary payload.

     Operating times for school contacts are planned into the crew's
activities.  The school contacts generate interest in science as students talk
directly with the astronauts.  There will be voice contacts with the general
ham community as time permits.  Shortwave listeners worldwide also may listen
in.  When the crew is not available, SAREX-II will be in an automated digital
response mode.

     SAREX-II will include VHF FM voice, VHF packet, VHF slow scan television
and UHF fast scan television.  The Space Shuttle has the built-in ability to
downlink television on any mission, but only SAREX-II has the ability to uplink
television to the crew.  During STS-50, fast scan television uplink was used to
send home videos of the crew members' families to the spacecraft, a specially
recorded message from Jay Leno and a specially recorded Houston television
sportscast.

     The primary voice and packet frequencies that SAREX-II uses are 145.55 MHz
downlink and 144.95 MHz uplink.  The 600 KHz spacing in the transmit and
receive frequency pair is compatible with amateur VHF equipment.  Since STS-56
is a high inclination flight, SAREX-II may be heard from northern Canada to
southern Australia and all points in between when the Shuttle is crossing
overhead.

     SAREX has previously flown on STS-9, STS-51F, STS-35, STS-37, STS- 45,
STS-50, STS-47 and STS-55. SAREX is a joint effort of NASA, the American Radio
Relay League (ARRL), the Amateur Radio Satellite Corp. (AMSAT), and the Johnson
Space Center's Amateur Radio Club. Information about orbital elements, contact
times, frequencies and crew operating schedules will be made available during
the mission by these agencies and by amateur radio clubs at some other NASA
centers.

     Hams from the Johnson Space Center club, W5RRR, will be operating on
amateur shortwave frequencies, and the ARRL station, W1AW, will include SAREX
information in its regular voice and teletype bulletins.  The amateur radio
station at the Goddard Space Flight Center, WA3NAN, in Greenbelt, Md., will
operate around the clock during the mission, providing information and
re-transmitting live Shuttle air-to-ground audio.

        The Johnson Space Center Public Affairs Office man a SAREX information
desk during the mission, and mission information also will be available on the
dial-up computer bulletin board (BBS) at JSC.

SAREX Frequencies       Shuttle Transmitting            Shuttle Receiving
                                  Frequency                          Frequency

U.S., Africa,          145.55 MHz                       144.95 MHz
South America,         145.55                           144.97
& Asia                 145.55                           144.91

Europe                 145.55 MHz                       144.95 MHz
                       145.55                           144.75
                       145.55                           144.70

GSFC Amateur Radio Club   (WA3NAN)  planned HF operating frequencies

3.860 MHz             7.185 MHz
14.295 Mhz            21.395 MHz
28.395 Mhz

To connect to the JSC Computer Bulletin Board, BBS, (8 N 1 1200 baud): dial
713/483-2500 then type 62511.



COMMERCIAL MDA ITA EXPERIMENTS

     More than 30 investigations will be conducted aboard Space Shuttle
Discovery to obtain information on how microgravity can aid research in drug
development and delivery, biotechnology, basic cell biology, protein and
inorganic crystal growth, bone and invertebrate development, immune
deficiencies, manufacturing processes and fluid sciences.

     The experiments represent the second flight of the Commercial MDA ITA
Experiments (CMIX-2) payload and should provide scientists and engineers with
some 400 data points from which they can focus and expand their research in
microgravity.

     NASA's Office of Advanced Concepts and Technology is sponsoring CMIX- 2,
with program management provided by the Consortium for Materials Development in
Space (CMDS), a NASA Center for the Commercial Development of Space (CCDS),
based at the University of Alabama in Huntsville (UAH).

     CMIX-2 is part of an innovative program between the UAH CMDS and ITA,
Inc., Exton, Penn., to provide the CCDS community with increased access to
space.  The program will use ITA-developed hardware on a total of five Shuttle
missions.  In exchange for the flight opportunities, ITA is providing 50
percent of its hardware capacity to the UAH CMDS.

     The CMIX-2 hardware consists of four Materials Dispersion Apparatus (MDA)
Minilabs, two of which will contain experiments developed by the UAH CMDS and
its industry affiliates.  The other two, commercially marketed by ITA, will
contain experiments developed by ITA's customers, which include U.S. biomedical
technology and biomaterials companies, international users and university
research institutions.

     A percentage of ITA's MDA capacity will include high school student
experiments as part of the company's Student Space Education Program to
increase awareness and interest in science and space technology.

     The MDA Minilab is a brick-sized, automated device capable of bringing
into contact and mixing up to 100 separate samples of multiple fluids and/or
solids at precisely timed intervals.  The MDA, which is housed in a Commercial
Refrigerator/Incubator Module (CRIM), uses four techniques for sample
contact/mixing, including liquid-to-liquid diffusion, vapor diffusion, magnetic
mixing and reverse gradient diffusion.

     In addition, live cell investigations will be conducted in ten
Bioprocessing Modules (BPM), which contain 60 to 100 times more fluid volume
than the MDAs. The BPMs will be flown "piggy back" using available space in the
CRIM, between the MDAs.

     The MDAs and BPMs each have a specific advantage to the research being
conducted on this flight.  The MDAs can process a number of experiments using
small volumes (0.2-0.5 milliliters) of sample materials.  On the other hand
each BPM can process only one or two experiments using a large volume (4-6
milliliters) of sample materials.

Experiment Descriptions

     Experiments developed by the UAH CMDS and its affiliates include:

     * Bone Cell Differentiation (MDA): Mouse bone cells will be evaluated on
how well they grow and produce collagen in microgravity.  Information from this
experiment will contribute to a database on potential areas for drug treatment
of osteoporosis.  Potential commercial applications (3-10 years) include
developing ways to enhance bone cell growth and prevent bone deterioration in
astronauts and the elderly.

     * Immune Cell Response (MDA): This experiment will obtain information on
why some cells are more sensitive to microgravity than others.  Once this is
understood, techniques may be developed to stimulate immune system cells for
use in treating immune suppressed patients and in developing and testing drugs
to reduce some of the undesirable effects of microgravity.

     * Diatoms (MDA): Minute plant cells (diatoms) encased in a silicone
coating can be used to generate oxygen.  This experiment will collect
information on how microgravity affects these one-celled plants to determine if
they can be used commercially to regenerate oxygen.

     * Mouse Bone Marrow Cells (MDA): This experiment will obtain information
on whether microgravity can enhance expansion of desirable cells by
manipulating them with growth factors.  Potential applications include bone
marrow transplants and reconstituting the immune system after radiation therapy
and chemotherapy treatments for leukemia, lymphoma and breast cancers.

     * Nerve/Muscle Cell Interactions: Using frog cells, this experiment will
study how microgravity affects the development of nerve cell communication
which is essential for brain function.  Results from this experiment may be
relevant to the ability of higher organisms to undergo normal brain development
in space.  Information from this experiment will increase a database on nerve
cell development in space, which will help to identify future potential
commercial applications.

     * Phagocytosis (MDA): To fight infection, one of the body's defenses is to
rid itself of invading organisms, such as bacteria, by the process of
phagocytosis (a means by which certain cells engulf and destroy foreign
materials).  This experiment will evaluate the phagocytic function of certain
cells in microgravity.  The expected long-range benefit is a better
understanding of the behavior of these disease-fighting cells.

     Other experiments conducted in the MDA will evaluate fluids mixing,
invertebrate and bone development, virus subunit assembly and collagen
self-assembly, and formation of drug encapsulated liposomes.  Commercial
applications of these experiments include developing a database for potential
commercial processes and services, which use individual cells to determine the
effects of microgravity and to develop and test drugs in space.  As the
database on cell response and control is enlarged, growth of commercial
applications can be expected.

     * Live Cell Investigations (BPMs): Experiments conducted in the BPMs are
designed to gain information on how cells of the human immune system may be
induced to grow when exposed to certain compounds.  Once scientists discover
how cells respond to these compounds in microgravity, techniques may be
developed to select for certain desirable cell types.  These cells types
produce factors (e.g., interferons) that stimulate other cells to grow and are
used to treat certain types of cancer.

     Experiments developed by ITA and its affiliates include:

     * Collagen Reconstitution (MDA): This experiment will study collagen
fibril growth in microgravity to develop unique and complex products that mimic
natural tissue structures.  Potential applications include corneal and
intraocular implants, bone repair materials and tendon/ligament grafts.

     * Microencapsulation (MDA): Drug microencapsulation techniques will be
studied to improve chemotherapy drug delivery, to encapsulate inhalant
medications and to enhance radiographic (x-ray) procedures.

     * Urokinase Protein Crystal Growth (MDA): Urokinase will be used to grow
crystals to help determine the enzyme's three-dimensional (3- D) structure for
use in developing a blocking or therapeutic drug that prevents the spread of
breast cancer.

     * Bacterial Aldolase and Rabbit Muscle Aldolase Protein Crystal Growth
(MDA): Two types of aldolase will be used to grow crystals to determine the
enzymes' 3-D structures for use in research on genetic illnesses.

     * HIV Reverse Transcriptase (MDA): Reverse Transcriptase will be used to
grow crystals to determine the enzyme's 3-D structure for use in AIDS research.

     * RNA Protein Crystal Growth (MDA): Ribonucleic acid (RNA) will be used to
grow crystals to determine the enzyme's 3-D structure for use in cell
pharmacology and in designing continuous catalytic reactors.

     * Methylase Protein Crystal Growth (MDA): This experiment will grow
crystals to study the interaction between methylase and deoxyribonucleic acid
(DNA) for use in identifying potential biomedical/biotechnology applications.

     * Lysozyme Protein Crystal Growth (MDA): Lysozyme will be used to grow
crystals to confirm the quality of flight conditions and to extend on- going
studies of lysozyme crystallization for biomedical applications.

     * DNA-Heme Protein Crystal Growth (MDA): This experiment will grow
crystals to study their 3-D structure for use in identifying potential
biomedical/biotechnology applications.

     * Brine Shrimp Development (MDA): Brine shrimp development will involve
hatching tiny Artemia Salina shrimp eggs in space to determine how microgravity
affects early development.  The shrimp are being studied as a potential space
food source.

     * Cell Research (MDA): This experiment will explore fluids and cell mixing
for cell culturing on Space Station Freedom.

     Other commercial MDA experiments include inorganic assembly (proprietary),
myoglobin protein crystal growth, dye and yeast cell diffusion, and engineering
tests.  Potential commercial applications are expected in areas such as
environmental sciences, drug research and development and cell pharmacology.
Engineering tests will be performed to obtain data on liquid-to-liquid
diffusion and magnetic mixing rates to verify normal MDA operations and provide
"baseline" diffusion data.

     * Mustard Seed Germination (MDA-student): Seeds and newly developing
reproductive tissue of Brassica Rapa will be flown.  The seeds will be dry and
the tissue will be immersed in an inert culture medium.  The materials returned
will be used to propagate successive generations of the plant to assess any
long-term effects on heredity patterns.  This is a follow- on to an STS-52
experiment.

     * Fish Egg Hatching (MDA-student): Using fish eggs, this experiment will
study how microgravity affects the hatching process of the annual killifish of
Zanzibar, Africa.

     * Heart Cells In Culture (MDA-student): Using heart cells, this experiment
will attempt to determine the effect(s) of microgravity upon the morphology and
rate of heart "beats" of heart muscle cells.

     * Mushroom Spore Generation (MDA-student): Using a selected strain of
Agaricus bisporus (the cultivated mushroom), this experiment will attempt to
determine the effect(s) of microgravity on the development of mushroom spores.
The spores then will be used as a comparison and later, lead to the eventual
growth of new and improved mushrooms.

     * Mustard-Spinach Seed Germination (MDA-student): This experiment will
attempt to determine the effects of microgravity on the mustard- spinach seed
germination process.  The germinated seeds will be compared with Earth-grown
sprouts.


On-orbit Operations

     The MDA minilabs each consist of an upper and lower block that contain a
matching number of "wells" (holes) filled with different substances.  The
blocks are aligned at launch so that the holes do not "line up" and the
materials in the wells do not touch each other.  When the proper microgravity
level is reached, the upper blocks will be moved in relation to the lower
blocks so the materials in matching wells come into contact to allow dispersion
(or mixing) of the different substance.

     To complete microgravity operations, the blocks again will be moved to
bring a third set of reservoirs to mix additional fluids or to fix the process
for selected reservoirs.  A prism window in each MDA allows the crew member to
determine the alignment of the blocks.

     To activate the MDAs, the crew will open the CRIM door to access the MDAs
and the MDA Controller and Power Supply. Activation will occur simultaneously
and is required as early as possible in the mission, followed by minimum
microgravity disturbances for a period of at least 8 hours.  The crew will
operate switches to activate each MDA, and once all the MDAs are activated, the
CRIM door will be closed.

     Deactivation of each MDA will occur automatically at different intervals.
For example, one MDA will automatically deactivate within minutes of being
activated, whereas one will not deactivate at all.  Deactivation of the other
two MDAs will occur later in the mission.  Once the Shuttle lands, the MDA
minilabs will be deintegrated and the samples will be returned to the
researchers for post-flight analyses.

     The crew also will activate the BPMs, which consist of four plastic
syringes.  The syringes are interconnected by tubing to a four-way valve
attached to an aluminum tray.  The first syringe of each BPM will contain live
cells.  The second syringe will contain a mediator of cell growth or function
(e.g., an activator), and the remaining two syringes will contain a chemical
fixative.

     To activate the BPMs, the crew will open the BPM valve to mix the cells
with growth mediator.  After specified times, the crew will terminate each BPM
test by turning the valve to mix cells with fixative to preserve cellular
structures in space before returning to Earth. Post-flight analyses will
evaluate cell growth and production of materials, including interferons.

     Principal Investigator for the CMIX-2 payload is Dr. Marian Lewis of the
UAH CMDS. John Cassanto, President, ITA, is Program Manager for the commercial
MDAs.

SPACE TISSUE LOSS-3 (STL-3)

Bone and Muscle Cell Culture Experiments

NASA Principal Investigator:
Emily R. Morey-Holton, Ph.D.
Ames Research Center, Mountain View, Calif.

U.S Army Principal Investigator:
George Kearney, Ph.D.
Walter Reed Army Institute of Research, Washington, D.C

     The musculoskeletal system is subjected to constant load by the
gravitational acceleration of the Earth. The structure and function of bone and
muscle tissue has been shaped throughout evolution by this constant stress.
The impact of diminution of this acceleration is not understood but may have
profound influence on the function of these gravity- related systems.

     Muscle tissue in space-flown animals and humans has been shown to respond
to exposure to the orbital environment by loss ofJcontractile protein,
alteration in the energy provision mechanisms within the cells and changes in
the structure of nerve/muscle interfaces.  When growing bones are unloaded in
space, bone growth is slowed; bones show delayed maturation which translates to
an increase in mass and mineralJcontent without the anticipated increase in
bone strength.

        The changes in the musculoskeletal system are most pronounced in, but
not limited to the weight-bearing limbs.  These changes hinder one's capability
to function when returning to Earth. The bone changes coupled with the decrease
in the mass of the gravity-dependent muscles make movement difficult, and the
individual may be prone to accidents because of this instability.

     The working hypothesis of the STL project is that the influence of gravity
is active at the level of individualJcells and that totally defined cellular
models of the changes noted in wholeJanimal preparations can be developed to
study the process at the molecular level.  The ultimate aim of the project is
to delineate the biochemical pathways and mechanisms responsible for the noted
changes and test the feasibility of pharmaceutical intervention to slow, arrest
or reverse the progress of the tissue loss.

     The current mission will be used to reproduce and verify the changes in
cell function observed in the two previous deployments on the Shuttle. Changes
in protein levels, enzyme activities and gene functions will be monitored.
Alteration in the morphology and nature maturation of the cells will be
determined upon return and followed for an extended period of recovery.  These
results will be compared to changes noted in space- flown whole animal function
to establish the validity and applicability of the cellular model.

     The significance of the current muscle cell experiments is threefold.
First, previous results have indicated that the process of development and
differentiation in cultured muscle satellite cells is impaired by an apparent
disruption of the ability of the precursor cells to fuse to form muscle fibers.
These cells function in the normal repair process for muscle so impact on the
ability of the cells to fuse is considered clinically significant.  Recovery of
muscle mass and strength following spaceflight might be hastened if these cells
are fully functional during the repair process in the muscle following return
to normal gravity.

     The second area of significance is the apparent stability of the changes
noted.  Space flown cells were unable to fuse for some 40 cell cycles following
return (35 days).  Ground control cells were 100 percent fused within 12 days.
Most reported alterations in cell function only have been shown to persist for
hours to days following return to normal gravity conditions.  Changes in the
function of the muscle cells are the most stable reported thus far.  If initial
observations are verified in the current experiment, these cells would allow
extensive ground-based study of the affects of space flight without the need
for constantly replenished supplies of experimental material that are changing
while the experiments are in process.

     A third area for potential application of data from this project is
satellite call therapy.  Disorders impacting muscle tissues such as the
muscular dystrophies are logical targets for gene replacement therapy.  The
gene involved in Duchenne muscular dystrophy is the largest known and delivery
with viral carriers is probably not feasible.  Generically altered satellite
cells currently are being studied for use as carriers for replacement genes.
This uses the natural reparative system of the muscle to effect restoration of
function.  The impairment of natural fusion potentially allows production of
therapeutically significant numbers of satellite cells from clones known to
express the desired genetic properties but without foreign surface antigens
which would necessitate immunosuppression of the transplant recipients.

     The significance of the bone cells experiment also is threefold.  Previous
results from STL have indicated that the metabolism of bone forming cells may
change during space flight and that mineralization of the bone fibers (matrix)
may be impaired.  Such changes at the whole bone level would cause decreased
bone strength.  The results will be repeated and expanded.  For example, the
type and amount of bone-specific products that the cells contain at the end of
this 8-day flight will be studied.  In addition, cells will be cultured upon
return to Earth to determine if the spaceflight induced changed can be reversed
after return to Earth.

     Finally, the amount and type of product found in the cell culture will be
compared to similar data being obtained in the whole rat (experiment PARE.03
below) to determine if spaceflight changes in bone cell cultures are similar to
those found in the animal.  Decrease in the activity of the bone forming cells
can alter the amount and type of bone formed and contribute to the changes in
bone strength.  Focusing on the initial event in the bone adaptation process by
analyzing cell changes during flight will help us determine if the changes at
the cellular level trigger the changes in bone strength.  Understanding what
gives bone its strength would be of great value in treating individuals at risk
for bone fracture or for better understanding why some people have weak bones.


PHYSIOLOGICAL AND ANATOMICAL RODENT EXPERIMENT.03

     The third Physiological and Anatomical Rodent Experiment (PARE.03) on
STS-56 is a secondary payload that will fly in a locker in the Space Shuttle's
mid-deck.

     PARE.03 consists of two experiments (PARE.03A and PARE.03B) with different
goals and different principal investigators.  Both will share the same group of
rats.  The goals of each experiment are fully compatible with the procedures
and goals of the other.  Both experiments endeavour to get new data that will
provide a cohesive view of bone biology during and following spaceflight.

Acute Adaptation of Bone to Spaceflight (PARE.03A)

Principal Investigator:
Emily R. Morey-Holton, Ph.D.
Life Science Division
NASA-Ames Research Center
Mountain View, Calif.

Co-Investigator: Russell T. Turner, Ph.D.
Department of Orthopaedics
Mayo Clinic
Rochester, Minn.

     The load imposed by Earth's environment throughout evolution has
determined the size, shape and strength of the skeletal system.  When growing
bones are unloaded on Earth or in space, bone growth is slowed. (In unloading,
the rat is placed in tail traction so its hind legs no longer bear weight.  The
rat can move freely using its front paws.  This technique simulates many, but
not all, of the effects of microgravity on rat bones.) Bones show delayed
maturation, which translates to an increase in mass and mineral content without
the expected increase in bone strength.

     The major hypothesis of this project is that gravity is necessary for
normal development of bone structure.  Another part of the hypothesis is that
decreased gravity or skeletal unloading causes defective skeletal growth.  This
defective growth is characterized by delayed maturation and increased bone mass
without increased bone strength.

     The proposed flight experiment is designed to confirm the bone defects
measured in past flight experiments.  These measurements include bone mass,
mineralization rates and strength at multiple sampling sites.  The experiment
also will focus on sites and molecular mechanisms of the growth defect.

     In addition, scientists will observe recovery from spaceflight to
determine if the defects are corrected by return to Earth after either 36 or 72
hours.  During the Space Shuttle mission, scientists on the ground will perform
the same experiment, using a ground-based rat model that simulates certain
aspects of spaceflight.  This will help determine the validity of this system
for predicting spaceflight responses in bone.

     PARE.03A is important for two reasons.  When individuals are exposed to
the microgravity of space or unloading on Earth, there appears to be a change
in bone structure.  In unloading, the rat is placed in tail traction so its
hind legs no longer bear weight, but the rat can move freely using its front
paws.  This technique simulates many of the effects of microgravity on rat
bones.

     Perhaps muscle no longer exerts enough force or bone, by itself, is not
stimulated to combine bone cell activity, cell products and mineral into a bone
structure that is as strong as a bone produced on Earth.

     Regardless of the cause, the changes in bone structure hinder one's
capability to function when returning to Earth. Movement patterns are
difficult, and the individual may be prone to bone fractures because of this
instability.  We need to find out what parts of the bone structure are changed.
We also need to determine the extent to which they change, the impact of the
changes on bone strength and how to prevent the changes from occurring.

     Second, unloading of the bones on Earth causes changes in the production
of various bone cell products.  Suggestions of similar changes have been
reported in rapidly growing rats during short-duration spaceflights.  The
altered products cause an imbalance of the normal ordered array of bone
structure, resulting in a weaker bone.  However, the imbalance may be different
during spaceflight than during unloading on Earth. If the imbalance is
different, then the mechanisms responsible for the weaker bone may be different
in space than on Earth. This would require different treatments to prevent the
changes.  Thus, one part of this flight experiment is an Earth-based experiment
on rats of the same age unloaded on Earth.

     The PARE.03A project will examine the extent to which the bone- forming
cells change their activity after exposure to microgravity for 8 days.  It also
will investigate whether these changes are reversed within 3 days of return to
Earth.

Cell Kinetic and Histomorphometric Analysis of Microgravitational Osteopenia
(PARE.03B)

Principal Investigator:
W. Eugene Roberts, D.D.S., Ph.D.
Co-Investigator:
Lawrence Garetto, Ph.D.
Departments of Orthodontics and Physiology/Biophysics
Indiana University Schools of Dentistry and Medicine, Indianapolis, Ind.
  The influence of gravity on the development and function of bone- forming
     cells (osteoblasts) is a basic biological question that may be common to
     many gravity-sensing organisms.  Because the production of bone-forming
     cells is mechanically sensitive, the force exerted by gravity is an
     important experimental variable for understanding mechanisms underlying
     osteoblast production.

     Gravity is a ubiquitous force that is inescapable on Earth. As such, all
Earth-bound organisms have evolved under the presence of this force.  Data from
both human and animal experiments suggest that exposure to the microgravity
environment of space may alter the normal "turnover" or renewal processes of
the skeletal bones.  Under normal conditions in Earth's gravity field, the
turnover process is the result of a balance between bone removal and bone
formation.  However, during spaceflight, bone formation is inhibited.  As a
result, the turnover of bone is unbalanced, resulting in a net loss.

     Previous experiments on both American and Russian missions have shown that
a lack of gravity appears to interfere with production of osteoblasts in
animals subjected to spaceflight.  This, in turn, ultimately may result in
reduced or altered capability to form bone mass in these animals.  Mechanical
force is known to influence the formation of preosteoblast cells.  The main
hypothesis of this experiment is that osteoblast production is blocked during
spaceflight but rapidly recovers within hours to days after return to Earth's
1-g environment.

     As mentioned previously, the process of normal osteoblast production may
have evolved with gravity as an essential co-factor.  This important question
is most effectively addressed by studying the effects of the removal of gravity
on different types of bone tissue.

     The PARE.03B experiment will examine how the lack of gravity encountered
during spaceflight affects the production of osteoblasts.  One goal is to use a
specific marker for DNA synthesis to examine preosteoblast cell proliferation.
This has not been done previously following spaceflight and will provide new
and unique data on the mechanism of osteoblast production.

     A second goal is to confirm previous data suggesting that preosteoblast
production is inhibited immediately following spaceflight.  The third goal of
this study is to determine if the block in osteoblast formation occurs
throughout the skeleton or if it is localized in specific types of bones.  This
will be measured by examining the process in different bones.  These include
the bones of the upper and lower jaw, which are non- weightbearing but
mechanically loaded in function; the shin bone (tibia), which is weightbearing
and the bones of the lower back.

     These vertebral bones differ from other bones in the rat in that they are
continuously undergoing a balanced turnover or renewal process.  In other
words, they undergo both removal by osteoclasts and new bone formation at other
sites by osteoblasts.

     Finally, a fourth goal is to determine how soon osteoblast production
recovers after return to Earth. Measurements made immediately following return
to Earth will be compared in animals allowed to recover for 36 and 72 hours.

     The PARE.03B experiment will provide basic insights into the cellular
mechanisms of the mechanical control of osteoblast production and function in
bone.  This kind of detailed knowledge at the cellular level may provide
biological insights into mechanisms underlying bone diseases in humans on
Earth. Bone diseases such as osteoporosis affect a large segment of society.
They result in billions of dollars in yearly health care and related costs due
to lost productivity.  Successful treatment of diseases such as these requires
a sufficient understanding of the basic biology of osteoblast production to
adequately and accurately develop treatment regimens.

     PARE.03B will provide additional short-term flight data to that already
collected on previous missions.  It will provide new information on
preosteoblast cell proliferation following spaceflight.  In addition, it will
extend our understanding of the recovery process of osteoblast production
following return to a 1g environment.  These experiments will yield answers to
basic biological questions about the ability of Earth-evolved animals to adapt
outside of their original evolutionary environment.  This will better enable us
to understand the role that mechanical force plays on Earth in maintaining our
skeleton.



     During spaceflight, changes have been noted in both the forelimbs and
hindlimbs of growing male rats.  Studies on the humerus and tibia have shown a
decrease in the amount of bone formed during flight.  In the cross sectional
area of bone depicted under "Bone Structure", a bone marker was given to the
animals prior to flight.  The marker forms the line inside the bone section.
The amount of bone formed during flight is the area between the marker and the
outer bone surface.

     During the same period of time, the ground animals form about 45 percent
more bone at the surface of the bone shaft.  If a similar area from each
section (boxes) is enlarged, further differences between the flight and ground
control rats can be seen.

     In the flight bone, surface blood vessels appear to be blocked with debris
and lipid deposits, the mineral may aggregate in smaller crystals and the
collagen may be some what disorganized in a convoluted pattern.  These changes
may be responsible for the changes in bone strength.  Data from the humerus,
femur and tibia suggest that the flight bone is about the same size as the
ground control bone, yet the amount of force required to break the bone is
significantly less in the flight animals (see "Bone Strength"). In fact, the
strength of the bone does not appear to increase as the bone increases in size,
suggesting that bone deposited during flight does not contribute to bone
strength.






STS-56 Crew Biographies

     Kenneth D. Cameron, 43, Col., USMC, is Commander of the second Atmospheric
Laboratory for Applications and Science (ATLAS) mission.  Selected to be an
astronaut in 1984, Cameron, from Cleveland, Ohio, is making his second Shuttle
flight.

     Cameron served as Pilot on Atlantis' STS-37 mission in April 1991 which
featured the deployment of the Gamma Ray Observatory.

     A graduate of Rocky River High School in Rocky River, Ohio, in 1967,
Cameron received bachelor and master of science degrees in aeronautics and
astronautics from the Massachusetts Institute of Technology in 1978 and 1979,
respectively.

     Cameron enlisted in the Marine Corps in 1969 and earned a commision in
1970 at Officer's Candidate School in Quantico, Va. He received his naval
aviator wings in 1973 and has logged over 3,400 hours flying time in 46
different types of aircraft.

     Stephen S. Oswald, 41, is the Pilot of STS-56. Selected as an astronaut in
1985, he was born in Seattle, Wash., but considers Bellingham, Wash., his
hometown.  He made his first flight as the Pilot aboard Discovery on STS-42 in
January 1992, an international microgravity laboratory mission.

     Oswald graduated from Bellingham High School, Bellingham, Wash., in 1969
and received a bachelor's degree in aerospace engineering from the Naval
Academy in 1973.  He was designated a naval aviator in September 1974 and flew
the Corsair II aboard the USS Midway in the Western Pacific and Indian Oceans
from 1975 through 1977.  In 1978, Oswald attended the Naval Test Pilot School.

     After leaving the Navy, he joined Westinghouse Electric Corp. as a test
pilot in developmental flight testing of various airborne weapons systems,
including the F-16C and B-1B radars.  Oswald remains active in the U.S. Naval
Reserve, currently assigned as Commanding Officer of the Naval Space Command
Reserve Unit, Dahlgren, Va. Oswald has logged more than 5,400 hours in 40
different aircraft and has logged over 193 hours in space.

     Michael Foale, Ph.D., 36, will serve as Mission Specialist 1 (MS1), making
his second space flight.  Selected as an astronaut in 1987, Foale considers
Cambridge, England, his hometown.

     Foale graduated from Kings School, Canterbury, England, in 1975.  He
attended the University of Cambridge, Queens' College, receiving a bachelor of
arts degree in physics in 1978.  He completed a doctorate in laboratory
astrophysics at Cambridge University in 1982.

     Prior to his selection as an astronaut in 1987, Foale worked for NASA as a
payloads officer in Mission Control at the Johnson Space Center, Houston. He
made his first space flight on STS-45, the first Atmospheric Laboratory for
Applications and Science flight.

     Kenneth D. Cockrell, 42, will serve as Mission Specialist 2 (MS2) and will
be making his first space flight.  Selected as an astronaut in 1990, Cockrell
considers Austin, Texas, his hometown.

     Cockrell graduated from Rockdale High School, Rockdale, Texas, in 1968,
received a bachelor of science degree in mechanical engineering from the
University of Texas in 1972 and a master of science degree in aeronautical
systems from the University of West Florida in 1974.

     Cockrell received a commission through the Naval Aviation Reserve Officer
Candidate program at the Naval Air Station in Pensacola, Fla., in 1972 and was
designated a naval aviator in 1974.  He has flown various types of aircraft and
has logged over 4,900 flying hours, including 650 aircraft carrier landings.

     Ellen Ochoa, Ph.D., 34, will serve as Mission Specialist 3 (MS3) on STS-
56.  She was born in Los Angeles, Calif., but considers La Mesa, Calif., her
hometown.  Selected as an astronaut in 1990, Ochoa will be making her first
space flight.

     Ochoa graduated from Grossmont High School in La Mesa in 1975.  She
received a bachelor of science degree in physics from San Diego State
University in 1980 and received a master of science degree and a doctorate in
electrical engineering from Stanford University in 1981 and 1985, respectively.

     Upon graduation from Stanford, Ochoa served on a research staff position
at Sandia National Laboratories, Livermore, Calif., specializing in work with
optical processing.  In 1988, she joined NASA's Ames Reserach Center, Moffett
Field, Calif., to work with optical recoginition systems for space automation.
At the time of her selection as an astronaut, Ochoa was serving as Chief of the
Intelligent Systems Technology Branch at Ames.



MISSION MANAGEMENT FOR STS-56

NATIONAL AERONAUTICS & SPACE ADMINISTRATION

NASA Headquarters, Washington, D.C.

Office of Space Flight

Jeremiah W. Pearson III - Associate Administrator
Bryan O'Connor - Deputy Associate Administrator
Tom Utsman - Space Shuttle Program Director
Leonard Nicholson - Space Shuttle Program Manager (JSC)
Col. Brewster Shaw - Deputy Space Shuttle Program Manager (KSC)

Office of Space Science and Applications

Dr. Lennard A. Fisk - Associate Administrator
Mr. Alphonso V. Diaz - Deputy Associate Administrator
Mr. Robert Benson - Director, Flight Systems Division
Dr. Shelby G. Tilford - Director, Earth Science and Applications Division
Dr. George Withbroe - Director, Space Physics Division
Mr. Paul DeMinco - Spartan-201 Program Manager
Mr. George Esenwein - ATLAS 2 Payload Manager
Dr. Jack Kaye - ATLAS 2 Program Scientist
Mr. Earl Montoya - ATLAS 2 Program Manager
Dr. William Wagner - Spartan-201 Program Scientist

Office of Safety and Mission Quality

Col. Frederick Gregory - Associate Administrator
Charles Mertz - (Acting) Deputy Associate Administrator
Richard  Perry - Director, Programs Assurance

Kennedy Space Center, Fla.

Robert L. Crippen - Director
James A. "Gene" Thomas - Deputy Director
Jay F. Honeycutt - Director, Shuttle Management and Operations
Robert B. Sieck - Launch Director
Dave King - Discovery Flow Director
J. Robert Lang - Director, Vehicle Engineering
Al J. Parrish - Director of Safety Reliability and Quality Assurance
John T. Conway - Director, Payload Management and Operations
P. Thomas Breakfield - Director, Shuttle Payload Operations

Marshall Space Flight Center, Huntsville, Ala.

Thomas J. Lee - Director
Dr. J. Wayne Littles - Deputy Director
Harry G. Craft, Jr. - Manager, Payload Projects Office
Teresa Vanhooser - Mission Manager, Atmospheric Laboratory for
                        Applications and Science - 2
Dr. Timothy Miller - Mission Scientist, Atmospheric Laboratory for
                        Applications and Science - 2
Alexander A. McCool - Manager, Shuttle Projects Office
Dr. George McDonough - Director, Science and Engineering
James H. Ehl - Director, Safety and Mission Assurance
Otto Goetz - Manager, Space Shuttle Main Engine Project
Victor Keith Henson - Manager, Redesigned Solid Rocket Motor Project
Cary H. Rutland - Manager, Solid Rocket Booster Project
Parker Counts - Manager, External Tank Project

Johnson Space Center, Houston

Aaron Cohen - Director
Paul J. Weitz - Deputy Director
Daniel Germany - Manager, Orbiter and GFE Projects
David Leestma - Director, Flight Crew Operations
Eugene F. Kranz - Director, Mission Operations
Henry O. Pohl - Director, Engineering
Charles S. Harlan - Director, Safety, Reliability and Quality Assurance

Stennis Space Center, Bay St. Louis, Miss.

Roy S. Estess - Director
Gerald Smith - Deputy Director
J. Harry Guin - Director, Propulsion Test Operations

Ames-Dryden Flight Research Facility, Edwards, Calif.

Kenneth J. Szalai - Director
Robert R. Meyers, Jr. - Assistant Director
James R. Phelps - Chief, Shuttle Support Office.

Goddard Space Flight Center, Greenbelt, Md

Dr. John Klineberg - Center Director
Thomas E. Huber - Director, Engineering Directorate
Robert Weaver - Chief, Special Payloads Division
David Shrewsberry - Associate Chief, Special Payloads Division
Jack Pownell - Spartan Mission Manager
Frank Collins - Spartan Project Manager
Richard Fisher - Spartan Principal Investigator



DEPARTMENT OF DEFENSE SECONDARY PAYLOAD MANAGEMENT


Key Management Partipants

Mission Director:  Lieutenant General Edward P. Barry, Jr., USAF,
     Commander, HQ Space and Missile Systems Center, Los Angeles AFB

Deputy Mission Director:  Colonel Robert H. Ballard, Program Manager,
     Space Test and Small Launch Vehicles Program, Hq, Space and Missile
     Systems Center, Los Angeles AFB

Assistant Deputy Mission Director:  Lt. Colonel James McLeroy,
     Executive Director, Operating Location AW (HQ Space and
     Missile Systems Center), at Johnson Space Center, Houston

USAF Secondary Payload Managers (JSC/OL-AW):

     Capt. David Goldstein
     Capt. Richard Martinez
     Capt. Reid Maier