From:STARS::HRSAKE 27-MAR-1990 18:47:47.10
To:6168::WARNOCK ! SENT TO @GHRSDIS
CC:
Subj:everything you'd EVER want to know about launch (except the date)

SPACE SHUTTLE MISSION STS-31
PRESS KIT

APRIL 1990



PUBLIC AFFAIRS CONTACTS

Ed Campion
Office of Space Flight
NASA Headquarters, Washington, D.C.
(Phone: 202/453-8536)

Paula Cleggett-Haleim
Office of Space Science and Applications
NASA Headquarters, Washington, D.C.
(Phone: 202/453-1548)

Barbara Selby
Office of Commercial Programs
NASA Headquarters, Washington, D.C.
(Phone: 202/453-2927)

Dwayne Brown
Office of Space Operations
NASA Headquaters, Washington, D.C.
(Phone: 202/453-8956)

Lisa Malone
Kennedy Space Center, Fla.
(Phone: 407/867-2468)

Kyle Herring
Johnson Space Center, Houston, Texas
(Phone: 713/483-5111)

Dave Drachlis/Jerry Berg
Marshall Space Flight Center, Huntsville, Ala.
(Phone: 205/544-0034)

Myron Webb
Stennis Space Center, Bay St. Louis, Miss.
(Phone: 601/688-3341)

Nancy Lovato
Ames-Dryden Flight Research Facility, Edwards, Calif.
(Phone: 805/258-8381)

Robert J. MacMillin
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone: 818/354-5011)

Jim Elliott
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-6256)


CONTENTS

GENERAL RELEASE
GENERAL INFORMATION
STS-31 QUICK LOOK
SUMMARY OF MAJOR ACTIVITIES
TRAJECTORY SEQUENCE OF EVENTS
SPACE SHUTTLE ABORT MODES
STS-31 PRELAUNCH PROCESSING
PAYLOAD AND VEHICLE WEIGHTS
HUBBLE SPACE TELESCOPE
Hubble Space Telescope and its Elements
Science Instruments
ORBITAL VERIFICATION
HST ACTIVATION IN DISCOVERY'S CARGO BAY
RELEASE OF HST
APERTURE DOOR OPENING THROUGH END OF OV/1
OV/2 FIRST WEEK
OV/2 SECOND WEEK
OV/2 THIRD WEEK
OV/2 FOURTH WEEK
OV/2 FIFTH WEEK THROUGH END OF OV/2
SCIENCE VERIFICATION
SCIENCE OPERATIONS
COMMAND, CONTROL AND OBSERVATION
TRACKING AND DATA RELAY SATELLITE SYSTEM
SPACE TELESCOPE OPERATIONS CONTROL
SPACE TELESCOPE SCIENCE INSTITUTE
EUROPEAN COORDINATING FACILITY
HUBBLE SPACE TELESCOPE SPECIFICATIONS
FUNCTIONAL DESCRIPTION OF HST OPERATIONS
SCIENCE QUESTIONS HST WILL HELP ANSWER
HUBBLE SPACE TELESCOPE PROGRAM HISTORY
NASA ESTABLISHES A TELESCOPE OFFICE
HST CONSTRUCTION TAKES A DECADE
MODULAR DESIGN ENHANCES MAINTENANCE
PROGRAM PARTICIPANTS COME FROM ALL OVER
HUNTSVILLE OPERATIONS SUPPORT CENTER
HST CONTRACTORS AND SUBCONTRACTORS
PROTEIN CRYSTAL GROWTH EXPERIMENT
INVESTIGATIONS INTO POLYMER MEMBRANE
PROCESSING 32
ASCENT PARTICLE MONITOR
RADIATION MONITORING EXPERIMENT
STUDENT SCIENCE INVESTIGATION PROJECT
IMAX
CREW BIOGRAPHIES
MISSION MANAGEMENT FOR HST LAUNCH
UPCOMING SPACE SHUTTLE MISSIONS (Graphic)
SPACE SHUTTLE FLIGHTS AS OF MARCH 1990 (Graphic)


GENERAL RELEASE

RELEASE: 90-44

DISCOVERY TO STATION HUBBLE SPACE TELESCOPE
IN EARTH ORBIT

Highlighting mission STS-31, the 35th flight of the Space Shuttle,
will be deployment in Earth orbit of the Hubble Space Telescope (HST).

HST, the largest on-orbit observatory ever built, is capable of
imaging objects up to 14 billion light years away. Unhampered by Earth's
atmospheric distortion, resolution of HST images is expected to be 7 to 10
times greater than images from Earth-based telescopes.

Orbiting at an altitude of 330 nautical miles, the telescope will
observe celestial sources such as quasars, galaxies and gaseous nebulae.
HST also will monitor atmospheric and surface phenomena of the planets in
Earth's solar system.

After launch, and once the payload bay doors are opened, the HST main
power busses will be activated allowing initial communications to be
established. This will begin a 90-day orbital verification period in which
the telescope will be checked to ensure that all systems are operational
and functioning. During this period, the crew cabin will be depressurized
in preparation for contingency activities that may arise related to the
telescope's deployment.

HST, which measures 43.5 feet long and 14 feet in diameter, is
scheduled to be deployed on the second day of the 5-day flight. Umbilical
disconnect is planned on orbit 16 followed by solar array extension and
slew tests on orbits 17 and 18. The high gain antennae boom deployment
also is scheduled for orbit 18. During HST checkout operations prior to
release from the remote manipulator system (RMS) arm, Mission Specialists
Bruce McCandless and Kathryn Sullivan will be prepared for an
extravehicular activity (EVA) if necessary.

The RMS will maneuver the telescope to the release position on orbit
19 with release scheduled for 1:47 p.m. EDT on April 13 based on a nominal
launch time. The IMAX Cargo Bay Camera will film various points of the
checkout and release of HST. Once HST is released, Discovery's crew will
maneuver the orbiter away from HST to a distance of about 40 nautical
miles. For the next 45 hours, the crew will trail HST in the event a
rendezvous and spacewalk are required in response to a failure during the
opening of the telescope's aperture door which protects the 94 1/2 inch
mirror -- the smoothest ever made. Activation of HST's six onboard
scientific instruments will follow aperture door opening on flight day
three, orbit 39. The remainder of the flight is reserved for middeck
experiment operations.

Joining HST in the payload bay will be the Ascent Particle Monitor to
measure particle contamination or particle detachment during the immediate
prelaunch period and during Shuttle ascent. Also in the payload bay is an
IMAX camera containing about 6 minutes of film. Discovery's middeck will
carry a variety of experiments to study protein crystal growth, polymer
membrane processing, and the effects of weightlessness and magnetic fields
on an ion arc.

Commander of the mission is Loren J. Shriver, Air Force Colonel.
Charles F. Bolden Jr., Marine Corps Colonel, will serve as pilot. Shriver
was pilot of Discovery's third flight, STS-51C in January 1985, the first
dedicated Department of Defense Shuttle mission. Bolden previously was
pilot of Columbia's seventh flight in January 1986.

Mission specialists are Steven A. Hawley, Bruce McCandless II and Dr.
Kathryn D. Sullivan. Hawley will operate and release HST from the RMS arm.
Hawley's previous spaceflight experience includes Discovery's maiden
voyage, STS-41D and Columbia's seventh flight, STS-61C. McCandless
previously flew on STS-41B, Challenger's fourth flight. Sullivan flew on
Challenger's sixth mission, STS-41G.

Liftoff of the tenth flight of Discovery is scheduled for 9:21 a.m.
EDT on April 12 from Kennedy Space Center, Fla., launch pad 39-B, into a
330 by 310 nautical mile, 28.5 degree orbit. Nominal mission duration is
expected to be 5 days 1 hour 15 minutes. Deorbit is planned on orbit 75,
with landing scheduled for 10:36 a.m. EDT on April 17 at Edwards Air Force
Base, Calif.

- END OF GENERAL RELEASE -


GENERAL INFORMATION

NASA Select Television Transmission

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

The schedule for tv transmissions from the orbiter and for the
change-of-shift briefings from Johnson Space Center, Houston, will be
available during the mission at Kennedy Space Center, Fla.; Marshall Space
Flight Center, Huntsville, Ala.; Johnson Space Center; Goddard Space Flight
Center, Greenbelt, Md. and NASA Headquarters, Washington, D.C. The
schedule will be updated daily to reflect changes dictated by mission
operations.

TV 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. Voice updates of the TV schedule may be obtained by dialing
202/755-1788. This service is updated daily at noon EDT.

Special Note to Broadcasters

In the 5 workdays before launch, short sound bites of astronaut
interviews with the STS-31 crew will be available to broadcasters by
calling 202/755-1788 between 8 a.m. and noon EDT.

Status Reports

Status reports on countdown and mission progress, on-orbit activities
and landing operations will be produced by the appropriate NASA news
center.

Briefings

An STS-31 mission press briefing schedule will be issued prior to
launch. During the mission, flight control personnel will be on 8-hour
shifts. Change-of-shift briefings by the off-going flight director will
occur at approximately 8-hour intervals.


STS-31 QUICK LOOK

Launch Date: April 12, 1990
Launch Window: 9:21 a.m. - 1:21 p.m. EDT
Launch Site: Kennedy Space Center, Fla.
Launch Complex: 39B

Orbiter: Discovery (OV-103)
Altitude: 330 circular
Inclination: 28.45
Duration: 5 days, 1 hour, 15 minutes

Landing Date/Time: April 17, 1990, 10:36 a.m. EDT

Primary Landing Site: Edwards Air Force Base, Calif.

Abort Landing Sites: Return to Launch Site -- KSC
TransAtlantic Abort - Ben Guerir, Morocco
Abort Once Around - Edwards AFB, Calif.

Crew: Loren J. Shriver - Commander
Charles F. Bolden Jr - Pilot
Steven A. Hawley - MS-2
Bruce McCandless II - MS-1 and EV1
Kathryn D. Sullivan - MS-3 and EV2

Cargo Bay Payloads: Hubble Space Telescope
IMAX Cargo Bay Camera

Middeck Payloads: Ascent Particle Monitor (APM)
Investigations into Polymer Membrane
Processing (IPMP)
Ion Arc (Student Experiment)
Protein Crystal Growth (PCG-III)



SUMMARY OF MAJOR ACTIVITIES

Day One

Ascent RMS checkout
Post-insertion DSO
Unstow cabin EMU checkout
10.2 cabin depress PCG activation

Day Two
HST deploy IMAX
DSO IPMP activation

Day Three
DSO/DTO Ion Arc (Student Exp)
IMAX RME Memory Module Replacement

Day Four
14.7 repress IMAX
DSO RME Memory Module Replacement

Day Five
AMOS PCG deactivation
DSO RCS hotfire
FCS checkout RME deactivation
IMAX Cabin stow

Day Six
DSO Deorbit burn
Deorbit preparations Landing at EAFB



TRAJECTORY SEQUENCE OF EVENTS

_________________________________________________________________

RELATIVE
EVENT MET VELOCITY MACH ALTITUDE
(d:h:m:s) (fps) (ft)
_______________________________________________________________

Launch 00/00:00:00

Begin Roll Maneuver 00/00:00:09 160 .14 605

End Roll Maneuver 00/00:00:15 313 .28 2,173

SSME Throttle Down to 67% 00/00:00:28 656 .58 7,771

Max. Dyn. Pressure (Max Q) 00/00:00:51 1,155 1.07 25,972

SSME Throttle Up to 104% 00/00:00:59 1,321 1.26 33,823

SRB Staging 00/00:02:06 4,145 3.77 159,670

Negative Return 00/00:04:06 7,153 7.15 341,470

Main Engine Cutoff (MECO) 00/00:08:33 24,768 23.18 361,988

Zero Thrust 00/00:08:39 24,783 22.65 366,065

ET Separation 00/00:08:51

OMS 2 Burn 00/00:42:38

HST Deploy (orbit 19) 01/05:23:00

Deorbit Burn (orbit 75) 05/00:03:00

Landing (orbit 76) 05/01:15:00

Apogee, Perigee at MECO: 325 x 27
Apogee, Perigee post-OMS 2: 330 x 310
Apogee, Perigee post deploy: 332 x 331


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 Edwards Air Force
Base, Calif.; White Sands Space Harbor (Northrup Strip), N.M.; or the
Shuttle Landing Facility (SLF) at Kennedy Space Center (KSC), Fla.

* Trans-Atlantic Abort Landing (TAL) -- Loss of two main engines midway
through powered flight would force a landing at Ben Guerir, Morocco; Moron,
Spain; or Banjul, The Gambia.

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

STS-31 contingency landing sites are Edwards AFB, White Sands, KSC,
Ben Guerir, Moron and Banjul. For a contingency return of Discovery with
the Hubble Space Telescope, conditioned purge air will be supplied to the
payload bay within 40 minutes after landing.


STS-31 PRELAUNCH PROCESSING

Shuttle processing activities at Kennedy Space Center for the
STS-31/Hubble Space Telescope mission began on Dec. 3, following the
orbiter Discovery's return to KSC after completion of the STS-33 mission of
November 1989.

During its 3-month stay in the Orbiter Processing Facility, Discovery
underwent some 36 modifications to its structural, flight and onboard
systems. These modifications included the installation of new carbon
brakes which will provide greater stopping power and control during
landing. The brakes have undergone extensive preflight testing at Wright
Patterson AFB in Ohio, with further testing to be conducted under actual
landings conditions. The high pressure oxidizer turbo pumps on Discovery's
main engines have been instrumented for the first time to provide data on
bearing wear. The data provided, along with a post-flight analysis of the
pumps, will help determine whether the pumps need to be rebuilt after each
flight as is currently the case. The location of Discovery's main engines
are the same as for the last mission: 2011 in the No. 1 position, 2031 in
the No. 2 position and 2107 in the No. 3 position.

The remote manipulator system was installed in Discovery's payload bay
and checked out during the first two weeks in January. The robot arm will
be used to deploy the Hubble Space Telescope.

Discovery's right aft solid rocket booster was replaced with one
designated for the STS-35 mission after data indicated that a critical leak
test had not been performed correctly on one of the internal joints. The
replacement was necessary because the location of the joint precluded
retesting at KSC. The assembled vehicle, atop mobile launcher platform 2,
was rolled out to Launch Pad 39B on March 15.

The Hubble Space Telescope arrived at KSC from the Lockheed Sunnyvale,
Calif. facility on Oct. 4, 1989, and began prelaunch testing in the
Vertical Processing Facility. It was powered up on Oct. 28 via satellite
command from Lockheed's HST control facility in Sunnyvale, beginning 40
days of functional testing of its operating systems and science
instruments. These tests included 11 days of on-orbit simulations via
satellite link with the Space Telescope Operations Control Center (STOCC)
at Goddard Space Flight Center, Greenbelt, Md.

The launch countdown is scheduled to begin 3 days prior to launch.
During the countdown, the orbiter's onboard fuel storage tanks will be
loaded and all orbiter systems will be configured for flight. About 9 hours
before launch, the external tank will be loaded with its flight load of
liquid oxygen and liquid hydrogen propellants.

Discovery is scheduled to land at Edwards AFB, Calif. KSC's landing
and recovery team at NASA's Ames-Dryden Flight Research Facility will
prepare the vehicle for its ferry flight back to KSC, expected to begin
approximately 5 days after landing.


PAYLOAD AND VEHICLE WEIGHTS

Vehicle/Payload Weight (pds)

Orbiter Discovery Empty 151,314

Remote Manipulator System (payload bay) 858

Hubble Space Telescope (payload bay) 23,981

Ascent Particle Monitor (payload bay) 47

IMAX system (payload bay) 374

DSO 77

DTO 289

HST middeck equipment 127

IMAX (middeck) 271

Investigation into Polymer Membrane Processing (IPMP) 17

Ion Arc (Student Experiment) 54

Protein Crystal Growth (PCG) 85

Radiation Monitoring Experiment (RME) 7

Orbiter and Cargo at main engine cutoff 259,229

Total Vehicle at SRB Ignition 4,516,325

Orbiter Landing Weight 189,477


HUBBLE SPACE TELESCOPE

The Hubble Space Telescope and its Elements

The HST weighs approximately 24,000 pounds, is 43 feet long, and 14
feet in diameter at its widest point. Roughly the size of a railroad tank
car, it looks more like two huge cylinders joined together and wrapped in
aluminum foil. Wing-like solar arrays extend horizontally from each side
of these cylinders, and dish- shaped antennas stretch out on rods above and
below the body of the telescope.

Many of the telescope's components are of modular design so they may
be removed and replaced in orbit by astronauts. Though other spacecraft
have received emergency repairs from Shuttle crews, the HST is the first
specifically designed for on-orbit servicing.

The HST is made up of three major elements: the support systems
module, the optical telescope assembly, and the scientific instruments.

The support systems module consists of the exterior structure of the
HST and the various systems that make it possible for the optical telescope
assembly and the scientific instruments to do their job.

The foil-like material with which the telescope is wrapped is actually
multi-layer insulation, part of the telescope's thermal control system.
The metallic silver surface reflects much of the direct sunlight which
strikes the telescope to keep it from overheating. Tiny heaters are
attached to many telescope components to warm them during the "eclipse"
phase of orbit, when in the Earth's shadow.

Electrical power for the HST is collected from the sun by the European
Space Agency's solar arrays. These two "wings" contain 48,000 solar cells.
They convert the sun's energy to electricity during the portion of orbit
that it is exposed to sunlight. The power is stored in six Nickel Hydrogen
batteries to support the telescope during eclipse.

When conducting an observation, the space telescope is rotated into
the proper orientation, then pointed to the star it is to view and locked
in place, by the pointing control system. This system is made up of a
complex series of gyroscopes, star trackers, reaction wheels and
electromagnets. The gyroscopes and reaction wheels are used to produce a
coarse pointing toward the star. That pointing is fine-tuned by star
trackers called fine guidance sensors. These sensors can locate and lock
on to a position in the sky to within 0.01 arc second and can hold that
pointing without varying more than 0.007 arc second for as long as 24
hours.

Also included in the support systems module are the computer which
controls the overall spacecraft; high-gain antennas which receive ground
commands and transmit data back to Earth; the electrical power system; the
structure of the telescope itself and its mechanical parts; and the safing
system, designed to take over control of the telescope to protect it from
damage in case of serious computer problems or loss of communication with
ground controllers.

The optical telescope assembly contains the two mirrors which collect
and focus light from the celestial objects being studied. The 94-inch
primary mirror is located near the center of the HST. Made of
precision-ground glass with an aluminum reflecting surface, it is the
smoothest large mirror ever made. To reduce weight, the front and back
plates are fused to a honeycomb core. The 13-inch secondary mirror is
located 16 feet in front of the primary mirror. It is set far enough
inside the open end of the telescope to assure that stray light does not
interfere with the image being studied. In addition, three black cylinders
called baffles surround the path of light to block out unwanted rays.

The two mirrors must remain in precise alignment for the images they
collect to be in focus. But the space environment is a hostile one. The
space telescope will experience wide variations in temperature as it passes
from the sun to shade portions of its orbit. Expansion and contraction
from the temperature extremes could easily cause the mirrors to go out of
focus. Therefore, the mirrors are made of a special kind of glass
formulated to resist that expansion and contraction. The telescope's
insulation blankets and solar-powered heaters will maintain them at 70
degrees Fahrenheit. In addition, the mirrors are held a precise distance
from one another by an extremely strong but lightweight truss structure.
The truss is made from graphite epoxy, a material also chosen for its
resistance to expansion and contraction in temperature extremes.

During observations, light from a celestial source travels through the
tube of the telescope to the large primary mirror. It is then reflected
from the primary mirror back to the secondary mirror. From there, the beam
narrows and intensifies, then passes through a hole in the center of the
primary mirror to a focal plane where the scientific instruments are
located.

The Hubble Space Telescope's scientific instruments are the Wide
Field/Planetary Camera, the Faint Object Camera, the Goddard High
Resolution Spectrograph, the Faint Object Spectrograph, and the High Speed
Photometer. The fine guidance system, in addition to being used for
pointing, also performs scientific measurements and is sometimes called the
sixth scientific instrument. Mounted on a focal plane almost five feet
behind the primary mirror, these scientific instruments will furnish
astronomers with a wide range of information about the stars and galaxies
they study. Each instrument is contained in a separate module and operates
on only 110 to 150 watts of power.

Science Instruments

The Wide Field/Planetary Camera (WF/PC) will be used to investigate
the age of the universe and search for new planetary systems around young
stars. It can compare near and far galaxies and observe comets such as
Halley's comet, which we previously could only view every 75 years. As its
name implies, the WF/PC can be used in two different ways. In its
wide-field mode, its field of view will allow it to take pictures of dozens
or even hundreds of distant galaxies at once. In the planetary mode, it
will provide close-ups of all the planets in our solar system except
Mercury, which is too close to the sun for safe pointing. The WF/PC can
observe larger areas of the sky and more different forms of light (from far
ultraviolet to near infrared) than any of the other science instruments.
It will also produce a greater volume of information for analysis than any
of the others.

Though its field of view is greater than that of any other Hubble
instrument, the "wide field" in this camera's name may be a little
misleading. Typical wide-field cameras at ground observatories have a
field of view of around 5 degrees. This camera's is only 2.67 arc minutes.
It would take a montage of about 100 "wide-field" images to get a picture
of the full moon. However, the narrower field of view allows much better
resolution of far-away objects.

Although it will focus on an even smaller area than its wide-field
counterpart, the Faint Object Camera (FOC) will extend the reach of the HST
to its greatest possible distance and produce its sharpest images. It will
be able to photograph stars five times farther away than is possible with
telescopes located on the ground. Many stars and galaxies, now barely
perceptible, will appear as blazing sources of light to the FOC. The
camera will intensify images to a brightness 100,000 times greater than
they were when received by the telescope. Then a television camera will
scan the intensified images and store them in the camera's memory for
transmission to the ground.

The FOC will be used to help determine the distance scale of the
universe, peer into the centers of globular star clusters, photograph
phenomena so faint they cannot be detected from the ground, and study
binary stars (two stars so close together they appear to be one). It is
part of the European Space Agency's contribution to the HST program.

Two spectrographs are also included in the HST's group of scientific
instruments. A spectrograph does not take a photograph of the image it
sees. Rather, one could say it takes its chemical "fingerprint." A
spectrograph separates the radiation received from an object according to
wavelengths, much as a prism splits visible light into colors. Every
chemical element produces its own individual pattern on a spectrogram. So
when the "fingerprint" of a certain element shows up on the spectrum,
scientists know that element is present in the object being viewed.
Scientists use spectrographs to determine the chemical composition,
temperature, pressure and density of the objects they are viewing.

The Faint Object Spectrograph (FOS) will be used to analyze the
properties of extremely faint objects in both visible and ultraviolet
light. It will be able to isolate individual light sources from those
surrounding them at very great distances. The FOS is equipped with devices
that can block out light at the center of an image so the much fainter
light around a bright object can be viewed. It will study the chemical
properties of comets before they get close enough to the sun for their
chemistry to be altered, as well as probing to see what the mysterious
quasars are made of. This instrument will offer comparisons of galaxies
that are relatively near Earth with those at great distances, helping
researchers determine the history of galaxies and the rate at which the
universe is expanding.

The Goddard High Resolution Spectrograph, though its work is similar
to that of its faint object companion, has a specialized job. It is the
only science instrument entirely devoted to studies of ultraviolet light.
Its detectors are designed to be insensitive to visible light, since the
ultraviolet emissions from starsare often hidden by the much brighter
visible emissions. The "high resolution" in this instrument's name refers
to high spectral resolution, or the ability to study the chemical
fingerprints of objects in very great detail. The combination of this
spectral resolution with the high spatial resolution of the cameras will
allow scientists to determine the chemical nature, temperature, and density
of the gas between stars. Its investigations will range from peering into
the center of far-away quasars to analyzing the atmospheres of planets in
our own solar system.

The High Speed Photometer, a relatively simple but precise light
meter, will measure the brightness of objects being studied, as well as any
variations in that brightness with time, in both the visible and
ultraviolet ranges. The photometer will be able to study the smallest
astronomical objects of any of the telescope's instruments. One of the
photometer's tasks will be to look for clues that black holes exist in
binary star systems. Variations in brightness would occur as one star
revolves around the other. Irregularities in that variation might indicate
that matter is being lost to a black hole--an object so dense that nothing,
not even light, can escape from it. The photometer will also provide
astronomers with an accurate map of the magnitude of stars.

The three fine guidance sensors serve a dual purpose. Two of the
sensors lock on to reference stars to point the telescope to a precise
position in the sky, then hold it there with a remarkable degree of
accuracy. The third sensor, in addition to serving as a backup unit, will
be used for astrometry -- the science of measuring the angles between
astronomical objects. These measurements will be combined with information
from other instruments to prepare a more accurate distance scale of the
universe.

ORBITAL VERIFICATION

HST's Orbital Verification (OV) program was established to verify that
its subsystems are functioning properly after it has been placed in Earth
orbit. As an extremely complex, precise and sensitive spacecraft, the HST
will require an extensive period of activation, adjustment and checkout
before it is turned over to the scientific community for their
investigations.

This process is thorough and methodical. It has been carefully
planned to assure that the telescope systems are not damaged during
activation and that the telescope itself and its ground support systems are
operating properly. Engineers and scientists will control this process
from the Space Telescope Operations Control Center (STOCC), at Goddard
Space Flight Center, Greenbelt, Md.

Orbital verification is divided into two phases. The first includes
deployment of the Hubble Space Telescope, activation of its systems, and
preliminary pointing and focusing. This phase is referred to as OV/1. A
team from the Marshall Space Flight Center will be stationed at the Goddard
Space Flight Center to manage this portion of verification. The Marshall
manager in charge of this team, referred to as the Director of Orbital
Verification (DOV), will give the final go-ahead for each step of the
carefully-scripted process. Another Marshall team working in Huntsville
will provide technical engineering support from the Huntsville Operations
Support Center (HOSC). Actual commands will be sent to the telescope by
Goddard mission operations personnel.

This first stage of orbital verification, OV/1, has four major goals:
fine-tuning pointing accuracy, focusing the telescope, initially activating
the scientific instruments and evaluating the performance of both the
telescope and ground control systems.

The second phase, referred to as OV/2, will be managed by Goddard,
with continued technical support furnished by Marshall. Activation and
calibration of the various science instruments, modes, as well as continued
refinements in alignment and focusing, will be accomplished during this
period.

The OV program is scheduled to last for about 90 days from time of
HST's deployment with the time divided roughly equally between the two
Orbital Verification phases.

HST ACTIVATION IN DISCOVERYUS CARGO BAY

The Shuttle crew will open Discovery's cargo bay doors shortly after
entering orbit. Then they will wait several hours to allow the air inside
the telescope to vent into space, reducing the possibility of electrical
arcing in some components when the main power is supplied to HST. After
the air has had time to escape, the DOV will give the go-ahead for
astronauts to switch on the main power from Discovery's aft flight deck.

Orbital verification is now officially underway and from this point
on, the telescope will be under direct control of the STOCC at Goddard.

Next, the DOV will authorize Goddard mission operations to send an
initial series of commands to the telescope. The telescope's communication
system will respond by sending information about the telescope's condition
to the STOCC. Mission operations then will confirm the telescope has
received the commands. Simultaneously, the technical support team in the
HOSC will evaluate the data from the telescope, verify the spacecraft is
responding properly to the commands, and verify that it is in the proper
configuration following launch.

Next, the OV team will begin a process called "thermal safing."
Spacecraft are exposed to a huge range of temperatures in orbit, from
blazing heat in direct sunlight to subfreezing temperatures during the
portion of their orbit when the Earth is between the craft and the sun.
Multi-layer insulation protects the telescope from the higher temperatures,
but without a heating system, components left exposed to space could freeze
in a short period of time. Thermal safing activates the telescope's
heaters and thermostats to assure the components do not suffer from these
external temperature extremes.

Toward the end of the orbiter's first day in space, the verification
team will activate HSTUs onboard command computer and check its memory. The
system which takes automatic control of the telescope in the event of loss
of communications with the ground (Safe Mode system) also will be
activated. While the Shuttle crew sleeps, the night shift at the STOCC
will be at work, monitoring and managing systems and preparing for removal
of the telescope from the cargo bay on the second day of the mission.

RELEASE OF HST

During the morning of the second day, DiscoveryUs crew will switch on
HST's internal power and deactivate the Orbiter-supplied power system. The
shuttle robot arm (Remote Manipulator System) will lift the Hubble Space
Telescope from the bay and suspend it above the crew cabin, with its door
pointed away from the sun.

The verification team will then send the signal to unfurl HSTUs solar
arrays almost immediately, so the telescope's six batteries can start
recharging. Next, the two high gain Tracking and Data Relay Satellite
System (TDRSS) antennas on the HST will be deployed.

Mission Specialists Bruce McCandless (MS1, EV1) and Kathy Sullivan
(MS3, EV2) will be standing by in their spacesuits ready to go outside the
spacecraft to manually provide these functions should the telescope fail to
respond correctly to ground commands.

Pointing systems will be activated to control the telescopeUs
orientation. Then, the remote manipulator arm will release its hold, and
the HST will float free in orbit. Following the telescope's release, the
Shuttle will back away into a parallel orbit to stand by for approximately
two days in case problems occur requiring corrective action by the
astronauts.

APERTURE DOOR OPENING THROUGH END OF OV/1

The telescope's aperture door must be opened next. After the OV
director is confident the instruments are reading correctly and that the
telescope is pointed away from the sun, HubbleUs light shield door will be
commanded open. Light from space will reach the telescope's
precision-ground mirrors for the first time.

The OV team will gradually adjust the position of the secondary mirror
until the images in the telescope's field of view become precise and sharp.
Several dozen exacting adjustments in the position of the mirror may be
required to further refine the focus and to compensate for the contraction
of the focal plane metering truss as desorption of water vapor occurs.

All of the individual components within each instrument require
specialized attention. Engineers at the STOCC will bring the instruments
up to full power and make sure they are operating properly. They also will
activate and evaluate the science computers which controls them. Actual
fine-tuning and calibration of the instruments is part of scientific
verification, but OV will not be over until the scientific instruments are
fully activated and ready for use.

About 6,200 specific items of information on the telescope's status,
called "telemetry points," are monitored by computer. Safe limits at any
given stage of activation for each individual telemetry point have been
established. Engineers from both the mission operations team at Goddard and
the Marshall technical support team at Huntsville will track systems in
their area of specialty. If any item does not perform within its predicted
limits it will be up to the OV team to determine if the problem is in the
telescope itself or in the ground system and then to decide how to resolve
it. With a system as unique and complex as the HST, it is almost
inevitable that some problems will arise. The purpose of OV is to catch
them before they grow into situations which could hamper telescope
performance.

OV/2 FIRST WEEK (BEGINS ABOUT HST DAY 45)

Engineering tests and calibrations will be performed to continue
optimizing instrument settings and operations. Aperture calibrations to
determine their precise locations also will be started. This set of
refinements begins the process of aligning each instrumentUs specific
aperture (a few thousandths of an arc-second field of view) within that
instrumentUs portion of the telescopeUs focal-plane field-of-view. .
Several instruments will monitor the effects of the South Atlantic Anomaly
(SAA) on instrument performance. This data will be used to decide the high
voltage turn-on sequences for the science instruments and to determine if
they will be able to continue data acquisition in the SAA.

The WF/PC will perform an activity to remove any contamination that
has possibly formed on the Charged Coupled Devices (CCD). Power will be
applied to the Thermal Electric Coolers (TEC) and the CCDs will be cooled
down to the proper operating temperature for science observations.

The FOC will perform its first external target observations on a star
for the purpose of aligning its apertures.

OV/2 SECOND WEEK

The STOCC team will continue monitoring the effects of the SAA on the
instruments. Instrument calibration and aperture alignment calibration
tests will be continued. The Faint Object Spectrograph (FOS) will perform
its first external target observations of a star to align its aperture.
The spacecraft's ability to perform an accurate continuous scan will be
assessed.

OV/2 THIRD WEEK

Tests and calibrations for instrument setting and aperture alignment
will continue. The WF/PC starts a series of observations that will assist
in defining the sharpness of images and the ability of the camera to
recognize two closely spaced images.

The Goddard High Resolution Spectrograph (GHRS) will perform its first
external target observations of a star to align its apertures.

Data will be taken which will be used to remove the non-uniformities
from WF/PCs images.

An HST thermal stability test will be performed to characterize the
telescope to establish the capability of the Fine Guidance Sensors (FGS) to
perform astrometry science.

OV/2 FOURTH WEEK

Tests and calibrations of the instruments continue. The FGS to FGS
alignment will be performed to provide more precise accuracy than was
achieved in OV/1. The alignment will improve the ability to establish the
proper science instrument (SI) calibrations. This activity, coupled with
the SI fine aperture alignment calibrations, which also are performed at
this time, give the spacecraft the calibration accuracy to start the more
stringent calibration activities.

These processes constitute a mid-point in what might be termed the
overall boresighting activities associated with determining the telescope
guidance system alignment, the telescope optical truss alignment,
individual instrument alignments and finally the overall system alignment.

The first FOS spectrum will be performed during the fine aperture
alignment calibration and the spiral search target acquisition capability
of the GHRS will be verified.

OV/2 FIFTH WEEK THROUGH END OF OV/2

Tests and calibrations of instruments continue. The optical distortion
in the FGS used most often for astrometry science will be measured to
provide a baseline for this FGS and the ability to do science with FGSs at
the required accuracy.

The long slit spectrographic mode of the FOC will be tested for the
first time.

SCIENCE VERIFICATION

After OV is completed, further calibration of the instruments and
evaluations of the telescope's performance will be accomplished. This next
effort will be carried out through the Space Telescope Science Institute.
During this period, astronomers who contributed to the telescope's design
will be given an opportunity to use the telescope to begin conducting their
research. However, only after scientific verification is complete will the
telescope be ready to begin its full-scale investigations.

Science Verification (SV) begins the phase of using the now-aligned
telescope instruments to test their performance capabilities. These
performance tests use specific astronomical targets for each instrument and
will provide a gauge of the HST instrumentUs performance compared with
results derived from previous, ground-based, observations of the same
target.

The SV process is lengthy and is expected to last through early Fall,
1990. During this time, as specific instruments are tested and their
performance capabilities recorded, some science observations will begin to
be made even though the entire suite of instruments may not yet be declared
operational.

SCIENCE OPERATIONS

Once the Hubble Space Telescope and its instruments have been fully
checked out and the entire system including ground data and computational
systems declared operational, HST operations will be turned over to the
Space Telescope Science Institute (STScI). The institute is located on the
Homewood campus of the Johns Hopkins University, Baltimore, Md.

Here, the science observing program has been developed, and it will be
from here that target selection and subsequent scientific observations
using HST will be performed. Although it is not necessary for the
investigators to be present at the STScI during their observations, space
for visiting scientists is available and a great number of astronomers are
expected to take up temporary residence during the time of their
observations.

COMMAND, CONTROL, OBSERVATION AND DATA SYSTEMS

The principal components of the command, control, observation and data
flow for the Hubble Space Telescope are:

%HST itself with its onboard computers and data systems;
%The Tracking and Data Relay Satellites (TDRS);
%The TDRS White Sands Ground Station (WSGT);
%Domestic communications satellites;
%The Goddard Network Operations Control Center (NOCC) at GSFC;
%NASA Communications System (NASCOM) at GSFC;
%The Space Telescope Operations Control Center (STOCC) at GSFC;
%The Space Telescope Data Capture Facility (STDCF) at GSFC;
%The Space Telescope Science Institute (STScI) at Baltimore;
%The Space Telescope European Coordinating Facility (ST-ECF);
%And ultimately the astronomers and scientists who use the data.

TRACKING AND DATA RELAY SATELLITE SYSTEM

The conduit that connects HST to the science community is the Tracking
and Data Relay Satellite System (TDRSS). There are two operational TDRS
satellites, one situated over the Pacific Ocean (TDRS-W) and one over the
Atlantic (TDRS-E). Without the TDRS system, HST would not be able to
conduct its observations.

HST is the first user to simultaneously require both Multiple Access
(MA) and S-band Single Access (SSA) return services from TDRSS. TDRSS will
continually transfer engineering data through the MA system to the STOCC at
Goddard. This service will be provided for up to 85 minutes of every HST
orbit that HST is in view of one of the TDRSS satellites.

TDRSS will also provide SSA forward and return services each orbit.
Realtime science and readouts of the HST onboard recorders will be
collected through the SSA return service. The SSA forward service will
allow the 12,000 commands executed by HST daily to be packaged and
transmitted to Hubble telescopeUs two onboard command computers controlling
the spacecraft.

HST will transmit almost three billion bits of information through the
TDRSS each day. This information is received at White Sands and forwarded
to the Goddard Data Capture Facility where it receives initial processing.

The data is then forwarded to the Space Telescope Science Institute.
There the science data is processed, calibrated and archived. Copies of
the archive tapes are provided to the European Coordinating Facility at
Noordwick, the Netherlands. American and European astronomers take the
data from either the Institute or the ECF back to their home institutions
for detailed processing and subsequent analysis.

The White Sands Ground Terminal, located at White Sands, New Mexico,
uses a pair of 16-foot (4.9 meter) diameter antennas to communicate with
the TDRS-W and TDRS-E in either S- or K-bands or both. It uses separate
antennas to receive and transmit the TDRSS data to other NASA controls
centers using leased domestic communications satellites.

SPACE TELESCOPE OPERATIONS CONTROL CENTER

The STOCC is located on the campus of the Goddard Space Flight Center
and operates as a dedicated spacecraft control center. It directly
communicates, through NASCOM and WSGT and the TDRS system, to the Hubble
telescope.

The STOCC contains a large number of redundant independent computer
systems. Each of the seven computer systems operates a portion of the
complex scheduling, configuring and commanding system which is required to
manage and run the HST. Separate systems located at the STScI work
directly with STOCC systems during realtime science operations with the
HST.

Within the STOCC is a separate sub-control center called the Mission
Operations Center (MOC). The MOC integrates the observing schedule for
each of HSTUs five instruments into a master schedule which includes TDRS
system availability. The MOC then originates the commands which direct the
movement of the HST for coverage of the various scientific targets.

SPACE TELESCOPE SCIENCE INSTITUTE

The Institute is both the starting point for observations and the
ending point for the data from those observations. In preparing an
observing calendar for HST, STScI planners arrange schedules to maximize
the science gain from the telescope. In all, STScI schedulers must
partition some 30,000 observations within the approximately 3,000 hours
available in any given 52-week observing cycle.

To aid in this scheduling, the Institute staff developed a tool
(Science Planning Interactive Knowledge Environment - SPIKE) to prepare
long- range calendars. What SPIKE does is to portray graphically the
various constraints imposed by HSTUs science instruments, the orbital
parameters of the spacecraft, the allocation of observing time for the
particular observation permitted under the peer review system and any
special requirements of the observer. SPIKE incorporates statistical and
artificial intelligence tools which then allows a best fit for the
observation and the available time.

The results of this planning are then fed into the Science Planning
and Scheduling System (SPSS). Here a second-by-second timeline is computer
generated to describe every detail of HSTUs science operation. The SPSS
then assembles the requests for commands which will be executed by the
telescopeUs onboard computer systems to carryout the observation. The
product of the SPSS is called a Science Mission Specifications file. This
product is then transmitted from the Institute to Goddard where it passes
through yet another computer system which converts the requests into the
actual binary code which will be uplinked to the spacecraft.

EUROPEAN COORDINATING FACILITY

Astronomers will also have access to HST data via the Data Archive and
Distribution System (DADS). The basic concept for this system is similar
to that used for the International Ultraviolet Explorer (IUE) and European
Exosat projects. As in these other projects, all raw and calibrated HST
data, upon receipt at the STScI, will be placed in the archives and will
become generally available once the original observerUs proprietary period
of access (normally a period of one year) has expired. A copy of the HST
data archives will be transmitted and kept at the European Coordinating
Facility (ST-ECF) where ESA Member-State astronomers will have full access
to it. The ECF is co-located at the European Southern Observatory (ESO)
located near Munich, Germany.


HUBBLE SPACE TELESCOPE SPECIFICATIONS

Main Mirror diameter 94.5 inches (2.4 meters)

Main Mirror weight 1,825 pounds (821 kilograms)

Main Mirror coating aluminum with 0.025 magnesium
fluoride over 70 % at hydrogen Lyman-Alpha

Main Mirror reflectivity 70 % at hydrogen Lyman-Alphawave
lengths and greater than 85 % at
visible wavelengths

Optical focal ratio f/24

Spacecraft length 43.5 feet (13.3 meters)

Spacecraft diameter
(with solar array stowed) 14.0 feet (4.3 meters)
(solar arrays deployed) 40.0 feet (12.0 meters)

Solar array size & power 7.9 by 39.9 feet (2.4 by 12.1 meters)
each average 2,400 watts electricity
production

Spacecraft weight 24,000 pounds (11,000 kilograms)

Orbital brightness -3 magnitude (Venus is -4.5, Jupiter is
-2.3, the Moon is -12.8)

Fine Guidance Measurement of position of a star to
System Capabilities within 0.002 arc-seconds

FUNCTIONAL DESCRIPTION OF HST OPERATIONS

Information and command flow from start to finish of an HST
observation is one of the most complex and interactive activities NASA has
yet undertaken in the realm of science operations.

Proposals first go the the Science Institute for review and selection.
Selected proposals are then transformed into requirements against HST
instrumentation and observation time. These requirements are then matched
with available spacecraft capabilities and time allocations. During this
process, a parallel activity matches the observation with necessary Rguide
starsS to serve as guidance system targets during the observation. This
process matches the field of view of the observation and its target with
available stars from the Guide Star Catalog(GSC). Following this process a
science observation schedule is developed and sent to Goddard.

At Goddard, the science observations schedules are matched with
spacecraft schedules and network tracking and data schedules. This
combined schedule is then converted into HST computer commands and then
sent to the the Payload Operations Control Center. From there the commands
travel through the NASA communications network to White Sands and then
through the TDRS system to the Hubble Space Telescope.

HST's onboard computer then executes the command sequence, moving the
spacecraft into position, turning on appropriate instruments and data
recording equipment and executing the observations. Data from the
observations is then sent back through the TDRS and NASA communications
system to Goddard. At Goddard the data is first captured in an interim
data storage facility and from there is transmitted to the Institute for
additional processing. Following the InstituteUs initial processing the
data is then calibrated and both archived and distributed to the scientist
whose observations it represents.

In tandem with these activities, the Goddard STOCC maintains an
updated computer file on both the performance of the Hubble spacecraft and
its exact orbital parameters. These are critical for the proper
development of the command sequences and for inertial reference.


SCIENCE QUESTIONS HST WILL HELP ANSWER

When HST is declared operational, sometime in the fall of 1990 if the
verification activities are accomplished satisfactorily, the astronomy team
associated with the project will be able to finally begin their full-scale
attack on some of astronomy and cosmologyUs toughest questions.

These questions are much the same fundamental questions which the
Renaissance philosophers, the Arab and before them the Egyptian and Mayan
astrologer/astronomers faced. They are simple questions: How big is the
universe? How old is the universe? Newer, but still simple, questions are
based on our understanding of Edwin P. HubbleUs pioneering work and that of
the Russian mathematician Alexander Friedman and the corroborating evidence
from Arno Penzais and Robert Wilson. These questions include will the
universe expand forever? What is the large scale structure of the
universe? And, is the universe homogeneous on a large scale. More
difficult but allied questions pertain to why normal matter (baryons) exist
at all. Why is matter seemingly smoothly distributed through the universe?
How did structure (galaxies) arise from a smooth homogenous fireball (big
bang)?

Some of these cosmological questions give rise to further, more
precise, questions. What is the Hubble Constant? TodayUs astronomical
observations give numbers which vary by a factor of two. The Hubble
Constant is a calculation of the rate at which space is expanding and is
expressed in kilometers per second per megaparsec (3.26 million light
years). Another question facing todayUs astronomers is what is the age of
the universe. This is calculated by taking the inverse of the Hubble
Constant . TodayUs numbers vary from 10 to 20 billion years of age. What
is the Deceleration Parameter? This is a measure of whether the distant
galaxies are receding at a slower rate than nearby (newer) galaxies and
would indicate a finite universe if the total pull of the matter in the
universe were sufficient to create a large Penzias - in effect slowing down
the expansion and perhaps ultimately causing a recollapse.

The expansion of the universe is controlled by the amount of matter
per unit volume (density). If the density is high enough, the expansion of
the universe will eventually slow and reverse. If the density is not high
enough then the universe will expand forever. The measure of the density
therefore becomes another critical element in our understanding the
evolution of the universe.

Hubble Space Telescope will contribute to answering these questions in
a variety of key observations. HST will be able to directly measure
Cepheid Variable stars out to 30 million light years. These stars are the
RmilepostsS by which distance is measured over vast distances. An accurate
measure of Cepheid Variables out to the distance of the Virgo Supercluster
(2,500 galaxies amassed together) will greatly extend reliable distance
measurements more than ten times than can be routinely done from ground
observations. HST will find Cepheid stars in a sample of about 50 galaxies
to arrive at an accurate measurement of the Hubble Constant.

The Hubble telescope also will enable astronomers to determine the age
of the universe by accurately measuring stars at distances much greater
than is now possible. Current cosmology has star formation occurring at a
period about one billion years (or so) after the Big Bang when the
temperature of the universe cooled sufficiently to allow atomic hydrogen to
form and begin condensing into stars. An accurate measurement of the ages
of the oldest stars will set a minimum age for the universe and therefore
help constrain the Hubble Constant.

Because HST is ideally suited for the task of resolving faint galaxies
at very high red shifts (a measure of recessional velocity and therefore
distance), it will also help in determining the deceleration rate of
distant galaxies. Before this technique can be applied, though, HST will
have to add to our knowledge about such distance galaxies since current
observations of these are so limited. Because such distant galaxies formed
much longer ago than nearby galaxies, their intrinsic luminosity and color
are not well understood which means they cannot reliably be used at the
present as a Rmilepost.S However, HST observations will contribute to the
intrinsic understanding of these galaxies and subsequent observations based
on new theories will allow potential use of these distant galaxies as
measuring devices for studies of deceleration.


By studying the motions of galaxies within clusters out to a distance
of nearly 100 million light years, HST astronomers will be able to infer
the mass of galaxies - both the light matter (stellar composition) and any
dark matter components. The resulting density measurements can then be
scaled up to compute the mass of the universe as a whole.

Acquiring answers to cosmological questions are a major reason for the
development and flight of the Hubble Space Telescope. There are, though, a
great many questions in the realm of astronomy and astrophysics which HST
will be addressing as well. A primary task for HST will be to trace the
evolution of galaxies and clusters of galaxies. Since HST will be able to
survey a volume of space nearly 100 times larger than can be surveyed with
comparable resolution from the ground, HST will help give us a picture of
what galaxies were like when the universe was only 35 percent of its
present age.

HSTUs high resolution will allow a survey for extra galactic black
holes. The imaging systems may be able to provide pictures of an accretion
disk in nearby galaxies and HST spectrometers will enable us to measure the
velocities of infalling gas thereby gauging the mass of suspected black
holes.

Hubble telescope's instruments should enable a breakthrough in our
understanding of synchrotron jets which extend for hundreds of thousands of
light years from the center of active galactic cores. For the first time,
these jets will be seen in ultraviolet light. These observations will be
matched with comparable resolution views taken with radio astronomy
observations.

Some of the questions pertaining to galaxies, quasi-stellar objects
(quasars or QSOs) and active galactic nuclei include:

%How soon after the Big Bang did galaxies form?
%How do galaxies evolve?
%What are the dynamics of galaxies in clusters?
%Do galaxies harbor massive black holes?
%What is the dark matter in a galaxy and how is it distributed?
%How important are galactic collisions in galaxy formation?
%What is the nature of starburst phenomena?
%What is the engine which powers quasars?
%What fuels the quasar engine?
%Are there new physics to be found powering the QSO engine?
%Do quasars represent a normal stage in galactic evolution?

Stellar physics questions to be addressed by HST include studying
white dwarfs. White dwarf stars are keys to our understanding the stages
of late stellar evolution. HST will aid in our present understanding of
this stage in a starUs life and answer questions such as, can stars
re-ignite after having ejected much of their mass late in their life.

At the other end of a starUs life, HST will image circumstellar disks
in star-forming regions to see how stellar activity affects the disks and
perhaps deduce what conditions are right for planetary system formation.

Solar physics and solar system evolution are major fields of
investigation for the HST astronomy team. Some of the questions HST will
help answer in these fields are:

%What is the precise sequence of steps in star formation?
%What determines the rate of star formation?
%How common are jets and disk structures in other stars?
%What is the mechanism that triggers nova-like outbursts in double stars?
%What are the progenitor stars to supernovas?
%Do circumstellar disks show evidence of planet building?
%Do planets exist about other stars?
%How abundant are other solar systems?
%What is the meteorology of the outer planets and how does it change over
time?
%What is the meteorology of Mars & what triggers the global summer dust
storms?
%How do the surface patterns of Pluto change over time?

HUBBLE SPACE TELESCOPE PROGRAM HISTORY

Long before mankind had the ability to go into space, astronomers
dreamed of placing a telescope above Earth's obscuring atmosphere. In the
heydays of the Roaring Twenties, German rocket scientist and thinker
Hermann Oberth described the advantages a telescope orbiting above Earth
would have over those based in observatories on the ground.

Scientific instruments installed on early rockets, balloons and
satellites beginning in the late 1940s produced enough exciting scientific
revelations to hint at how much remained to be discovered. In the
technology era spawned by the end of World War II, Dr. Lyman Spitzer, Jr.,
an astronomer at Princeton University, advanced the concept of an orbiting
instrument of the Mount Wilson Observatory.

The first official mention of an optical space telescope came in 1962,
just four years after NASA was established, when a National Academy of
Sciences study group recommended the development of a large space telescope
as a logical extension of the U.S. space program.

This recommendation was repeated by another study group in 1965.
Shortly afterwards the National Academy of Sciences established a
committee, headed by Spitzer, to define the scientific objectives for a
proposed Large Space Telescope with a primary mirror of about 10 feet (or
120 inches).

Meanwhile, the first such astronomical observatory--the Orbiting
Astronomical Observatory-1, already had been launched successfully in 1968
and was providing important new information about the galaxy with its
ultraviolet spectrographic instrument.

In 1969 the Spitzer group issued its report, but very little attention
was paid to it by the astronomy community. At that time quasars, pulsars
and other exotic cosmic phenomena were being discovered and many
astronomers felt that time spent working towards a space telescope would be
less productive than their existing time in ground-based observatories.

A 1972 National Academy of Sciences study reviewed the needs and
priorities in astronomy for the remainder of that decade and again
recommended a large orbiting optical telescope as a realistic and desirable
goal. At that same time, NASA had convened a small group of astronomers to
provide scientific guidance for several teams at the Goddard and Marshall
Space Flight Centers who were doing feasibility studies for space
telescopes. NASA also named the Marshall center as lead center for a space
telescope program.

NASA ESTABLISHES A TELESCOPE OFFICE

NASA established in 1973 a small scientific and engineering steering
committee to determine which scientific objectives would be feasible for a
proposed space telescope. The science team was headed by Dr. C. Robert
O'Dell, University of Chicago, who viewed the project as a chance to
establish not just another spacecraft but a permanent orbiting observatory.

In 1975 the European Space Agency became involved with the project.
The O'Dell group continued their worked through 1977, when NASA selected a
larger group of 60 scientists from 38 institutions to participate in the
design and development of the proposed Space Telescope. In 1978 Congress
appropriated funds for the development of the Space Telescope.

NASA assigned responsibility for design, development and construction

of the space telescope to the Marshall Space Flight Center in Huntsville,
Ala. Goddard Space Flight Center, Greenbelt, Md., was chosen to lead the
development of the scientific instruments and the ground control center.

Marshall selected two primary contractors to build the Hubble Space
Telescope. Perkin-Elmer Corporation in Danbury, Connecticut, was chosen
over Itek and Kodak to develop the optical system and guidance sensors.
(Though Kodak was later contracted by P-E to provide a backup main mirror
blank, which it did and which is now in storage at Kodak, Rochester, N.Y.)
Lockheed Missiles and Space Company of Sunnyvale, California, was selected
over Martin Marietta and Boeing to produce the protective outer shroud and
the support systems module (basic spacecraft) for the telescope, as well as
to assemble and integrate the finished product.

The European Space Agency agreed to furnish the spacecraft solar
arrays, one of the scientific instruments and manpower to support the Space
Telescope Science Institute in exchange for 15% of the observing time and
access to the data from the other instruments. Goddard scientists were
selected to develop one instrument, and scientists at the California
Institute of Technology, the University of California at San Diego and the
University of Wisconsin were selected to develop three three other
instruments.

The Goddard Space Flight Center normally exercises mission control of
unmanned satellites in Earth orbit. Because the Hubble Space Telescope is
so unique and complex, two new facilities were established under the
direction of Goddard, dedicated exclusively to scientific and engineering
operation of the telescope. The facilities are the Space Telescope
Operations Control Center at Goddard and the Space Telescope Science
Institute, on the grounds of the Johns Hopkins University, Baltimore, Md.

The Space Telescope Operations Control Center, or STOCC as it is
called, is located in a wing of Building 14 on the Goddard campus. It was
established in 1985 as the ground control facility for the telescope. The
scientific observing schedule developed by the Science Institute will be
translated into computer commands by the control center and relayed via the
Tracking and Data Relay Satellite System to the orbiting telescope. In
turn, observation data will be received at the center and translated into a
format usable by the Science Institute. The control center also will
maintain a constant watch over the health and safety of the satellite.

The Space Telescope Science Institute was dedicated in 1983 in a new
facility near the Astronomy and Physics Departments of Hopkins. It will
perform the science planning for the telescope. Scientists there will
select observing proposals from various astronomers, coordinate research,
and generate the telescope's observing agenda. They also will archive and
distribute results of the investigations. The Institute is operated under
contract to NASA by the Association of Universities for Research in
Astronomy (AURA) to insure academic independence. It operates under
administrative direction of the Goddard center.


TELESCOPE CONSTRUCTION TAKES DECADE TO ACCOMPLISH

Construction and assembly of the space telescope was a painstaking
process which spanned almost a decade. The precision-ground mirror was
completed in 1981, casting and cooling of the blank by Corning Glass took
nearly a year . The optical assembly (primary and secondary mirrors,
optical truss and fine guidance system) was delivered for integration into
the satellite in 1984. The science instruments were delivered for testing
at the Goddard center in 1983. Assembly of the entire spacecraft at the
Lockheed Sunnyvale facility was completed in 1985.

Launch of the Hubble Space Telescope was originally scheduled for
1986. It was delayed during the Space Shuttle redesign which followed the
Challenger accident. Engineers used the interim period to subject the
telescope to intensive testing and evaluation, assuring the greatest
possible reliability. An exhaustive series of end-to-end tests involving
the Science Institute, Goddard, the Tracking and Data Rel system and the
spacecraft were performed during this time, resulting in overall
improvements in system reliability.

The telescope was shipped by Air Force C5A from Lockheed, Sunnyvale,
to the Kennedy Space Center, Florida in October 1989.

From 1978 through launch, the Space Telescope Program has cost $1.5
billion for the development, design, test and integration of the Hubble
Space Telescope and associated spacecraft elements, $300 million for the
science and engineering operations which have been supporting both the
spacecraft development and the ground science operations at Goddard and the
Space Telescope Science Institute, and $300 million for the design,
development and testing of servicing equipment to maintain the Telescope's
15-year expected lifetime.

The Hubble Space Telescope was designed specifically to allow
extensive maintenance in orbit. This is the most practical way to keep the
equipment functioning and current during its 15 years or more in space with
a minimum of down time. Some of the components such as batteries and solar
arrays have a life expectancy shorter than 15 years and will need to be
replaced from time to time. New technology will make it possible to design
more sophisticated scientific instruments over the years. Several new
generation instruments are already under development. In-orbit servicing
allows worn parts to be replaced and new instruments to be substituted for
the original equipment without the great expense, risk and delay of
bringing the telescope back to Earth.

MODULAR DESIGN ENHANCES MAINTENANCE AND UPGRADABILITY

The modular design of many space telescope components means that units
may be pulled out and a replacement plugged in without disturbing other
systems. Doors on the exterior of the telescope allow astronauts access to
these modular components, called Orbital Replacement Units. Handrails and
portable foot restraints make it easier for them to move about in the
weightless environment while working on the telescope. A special carrier
has been designed to fit in the orbiter's cargo bay to hold replacement
parts and tools.

Astronauts will visit the space telescope every three to five years on
servicing missions. In case of an emergency, special contingency rescue
missions have been partially developed and could be mounted between the
scheduled visits.

On servicing missions, the Space Shuttle will rendezvous with the
orbiting telescope. Astronauts will use the Shuttle's remote manipulator
arm to pull in the observatory and mount it on a maintenance platform in
the orbiter's payload bay. Astronauts will don space suits and go out into
the bay to complete required maintenance. They may change out batteries or
solar arrays, a computer, one of the scientific instruments, or any of the
more than 50 units that can be replaced in orbit. The Shuttle also may be
used to carry the telescope back to its original orbital altitude if
atmospheric drag has caused it to descend.

Once the maintenance is finished, the telescope will be released once
more as a free flyer. A ground team reactivation will then take place so
the telescope again can resume its exploration tasks.

PROGRAM PARTICIPANTS COME FROM ALL OVER

The Hubble Space Telescope is the product of not just one group or
agency, but a cooperative effort of many dedicated people from across the
United States and around the world. Following is a brief summary of the
institutions that are a part of the Hubble Space Telescope Program and
their contributions:

NASA Headquarters Astrophysics Division, Office of Space Science and
Applications, Washington, D.C.: Overall direction of the Hubble Space
Telescope Program.

Marshall Space Flight Center, Huntsville, Alabama: Overall management
for Hubble Space Telescope project, including supervision of design,
development, assembly, pre-launch checkout and orbital verification.

Goddard Space Flight Center, Greenbelt, Maryland: Development of the
scientific instruments, day-to-day operation of the telescope through its
Space Telescope Operations Control Center and oversight of the Space
Telescope Science Institute on the campus of Johns Hopkins University in
Baltimore, Maryland.

Johnson Space Center, Houston, Texas: Orbiter and crew services
during deployment and maintenance missions.

Kennedy Space Center, Florida: Pre-launch processing and Space
Shuttle launch support, assuring safe delivery of the telescope to orbit.

European Space Agency: Provision of the solar arrays and Faint
Object Camera, operational support at the Science Institute and maintenance
of a data distribution and archive facility in Europe; in return ESA is
allocated 15 percent of telescope observing time.

Universities whose staff members have made major contributions to the
program include:

California Institute of Technology, Pasadena: Wide Field/Planetary
Camera, Dr. James Westphal, Principal Investigator;

University of California at San Diego, La Jolla: Faint Object
Spectrograph, Dr. Richard Harms, Principal Investigator (now with Applied
Research Corp., Landover, Maryland);

University of Colorado, Boulder: Dr. John C. Brandt, Principal
Investigator for the Goddard High Resolution Spectrograph.

University of Texas, Austin: astrometry (using the Fine Guidance
System), Dr. William H. Jefferys, Principal Investigator;

University of Wisconsin, Madison: High Speed Photometer, Dr. Robert
Bless, Principal Investigator.

HUNTSVILLE OPERATIONS SUPPORT CENTER
HST TECHNICAL SUPPORT TEAM

A team of technical experts at NASA's Marshall Space Flight Center,
Huntsville, Ala., will monitor the Hubble Space Telescope's engineering
performance during its deployment and activation to confirm whether ground
commands sent to the telescope have had their desired result. They will
help identify problems which may arise, analyze them and recommend
solutions.

The Hubble Space Telescope Technical Support Team is composed of
representatives of the agencies and companies which designed and built the
space telescope. They will be stationed in Marshall's Huntsville
Operations Support Center during orbital verification.

The data that the telescope sends back to Earth (called "telemetry")
will be simultaneously monitored by engineers in the Space Telescope
Operations Control Center at Goddard and by the technical support team in
Huntsville. The Goddard group will use this information to track progress
in implementing the verification schedule and to make short-term
operational decisions. The Marshall team will track the telescope's status
and engineering performance.

Support Team Responsibilities - Technical support team engineers have
three major assignments:

First, they will monitor telescope telemetry, tracking several
thousand engineering measurements to determine the ongoing status of the
HST and to confirm whether the telescope has responded properly to ground
commands sent from the control center at Goddard. With the information
they receive, they can identify problems if they arise.

Second, they will use their in-depth knowledge of the telescope and its
systems to analyze problems and recommend ways to resolve them. This will
include problems identified at Goddard and assigned to the Huntsville team
for analysis, as well as those discovered by the technical support group
and reported to the orbital verification management team at the Space
Telescope Operations Control Center at Goddard.

Third, they will evaluate the performance of the space telescope to
determine its true capabilities and project its future performance.

Discipline Teams - Instead of being grouped by agencies and companies,
the technical support team will be organized by specialty into ten
discipline or subsystem teams. Team members will include civil service and
contractor employees with expert knowledge of their particular Hubble Space
Telescope subsystem.

Each contractor/government team will be led by a NASA engineer charged
with accomplishing the three support team goals: problem analysis and
resolution, evaluation of current performance and development of long-range
predictions for the capabilities of the telescope system. Engineering
specialists representing the companies which developed the system will also
be part of the team. Each group will be assigned a conference work area
where they can monitor current or past telescope telemetry and complete
problem analyses.

Engineering Console Room - The "eyes and ears" of the technical
support team will be provided by personnel in the engineering console room.
Engineers stationed there from each discipline team will continuously
monitor "real-time" telemetry (that currently being sent from the
telescope). The current value of hundreds of different measurements
concerning their assigned subsystem will be displayed on their computer
screens. Some types of measurements to be tracked are temperature,
velocity, time, position, current and voltage.

Each measurement has been assigned a safe limit for every stage of
activation. For instance, at a stated time, a designated heat sensor
should register a specified temperature. If the measurement begins to move
outside its safe range, the screen it appears on will flash yellow to
indicate the problem. If the limits are passed even further, the screen
will flash in red. About 200 measurements may be identified as critical
for any point in activation or operation. When these approach the limits,
a message will flash on all the terminals, regardless of discipline.

Method of Operation - Computer screens will be monitored
simultaneously from the Goddard missions operations room and the Huntsville
conference work areas and engineering console room. A situation requiring
attention may be first detected at any of these locations.

Once a problem is identified, the discipline teams will go into action
to track down its cause. First, they will determine if there is a real
malfunction in the telescope or if the computer software is showing an
erroneous measurement. If the problem is with the telescope itself, an
approach to resolving it will be formulated between the management group at
Goddard and the technical support team.

Contingency plans, designed in advance for dealing with possible
problems, will be reviewed. Discipline teams will analyze current and past
data from the telescope, as well as their design records. Based on that
research and their in-depth knowledge of the system, the discipline teams
will recommend a solution to systems engineers in the action center. The
action center management group will evaluate and consolidate the
recommendation and pass it on to the orbital verification management team
at Goddard.

Technical Support Team Participants - The 175-member Hubble Space
Telescope Technical Support Team is made up of personnel from the Marshall
Space Flight Center, Lockheed Missiles and Space Company, Hughes Danbury
Optical Systems (formerly Perkin-Elmer) and the European Space Agency.


HST CONTRACTORS AND SUBCONTRACTORS

Optical Telescope Assembly Hughes Danbury Optical Systems
and Fine Guidance Sensors Danbury, Conn.

Primary Mirror blank Corning Glass Works
Corning, N.Y.

Mirror Metering Truss Boeing Airplane Co.
Seattle, Wash.

Support Systems Module Lockheed Missiles & Space Co.
(spacecraft) and integration Sunnyvale, Calif.

Solar Arrays British Aerospace Public Ltd. Co
Bristol, England, U.K.

Science Instrument Command Fairchild Space Company
and Data Handling Computer Germantown, Md.

Wide Field & Planetary Camera NASA Jet Propulsion Laboratory
Pasadena, Calif.

CCD arrays for WF/PC Texas Instruments
Dallas, Texas

Faint Object Camera Dornier GmbH
Friedrichshafen, FRG

Faint Object Spectrograph Martin Marietta Corp.
Denver, Colo.

Goddard High Resolution Ball Aerospace
Spectrograph Boulder, Colo.

High Speed Photometer University of Wisconsin
Madison, Wisc.

Space Telescope Operations Lockheed Missile & Space Co.
Control Center Sunnyvale, Calif.
Ford Aerospace & Comm. Co.
College Park, Md.

Network and Mission Bendix Field Engineering
Operations Support Columbia, Md.

Science Operations Ground TRW, Inc.
Systems Redondo Beach, Calif.

Computer system software Computer Sciences Corp.
Silver Spring, Md.

Light Shade, Magnetic Bendix Corporation
Torquer & Sensing System, Greenbelt, Md.
Safemode Electronics

PROTEIN CRYSTAL GROWTH EXPERIMENT

The Protein Crystal Growth (PCG) payload aboard STS-31 is a
continuing series of experiments leading toward major benefits in
biomedical technology. These experiments are expected to improve food
production and lead to innovative new drugs to combat cancer, AIDS, high
blood pressure, organ transplant rejection, rheumatoid arthritis and many
other medical conditions.

Protein crystals, like inorganic crystals such as quartz, are
structured in a regular pattern. With a good crystal, roughly the size of
a grain of table salt, scientists are able to study the protein's molecular
architecture.

Determining a protein crystal's molecular shape is an essential step
in several phases of medical research. Once the three-dimensional
structure of a protein is known, it may be possible to design drugs that
will either block or enhance the protein's normal function within the body
or other organisms. Though crystallographic techniques can be used to
determine a protein's structure, this powerful technique has been limited
by problems encountered in obtaining high-quality crystals well ordered and
large enough to yield precise structural information.

Protein crystals grown on Earth are often small and flawed. The
problem associated with growing these crystals is analogous to filling a
sports stadium with fans who all have reserved seats. Once the gate opens,
people flock to their seats and in the confusion, often sit in someone
else's place. On Earth, gravity-driven convection keeps the molecules
crowded around the "seats" as they attempt to order themselves.
Unfortunately, protein molecules are not as particular as many of the
smaller molecules and often are content to take the wrong places in the
structure.

As would happen if you let the fans into the stands slowly,
microgravity allows the scientist to slow the rate at which molecules
arrive at their seats. Since the molecules have more time to find their
spot, fewer mistakes are made, creating more uniform crystals.

Protein crystal growth experiments were first carried out by the
investigating team during STS 51-D in April 1985. These prototype
experiments were flown four times and were primarily designed to test vapor
diffusion techniques and sample handling apparatus.

The STS-26 PCG was the first controlled or systematic experiment to
grow useful crystals by vapor diffusion in microgravity within a thermal
control enclosure -- the Refrigerator/Incubator Module (R/IM). This
equipment was also flown aboard STS-29 and STS-32. Crystals were grown at
cold temperatures for the first time on STS-32, demonstrating the potential
for using longer flights to process certain proteins.

Results from these experiments have been encouraging, with high
quality crystals developing from several of the samples flown. Generally,
these crystals are of exceptional size and/or quality when compared to
control samples grown in gravity.

During the STS-31 mission, 60 different PCG experiments will be
conducted simultaneously using 12 different proteins. These proteins are:

*Isocitrate Lyase -- a target enzyme for fungicides. Better
understanding of this enzyme should lead to more potent fungicdes to treat
serious crop diseases such as rice blast.

*Porcine Pancreatic Phospholipase A2 -- an enzyme associated with
many human disease states including rheumatoid arthritis and septic shock.
Successful structure analyses of phospholipase crystal may lead to
development of drugs to treat these conditions.

*Human Gamma Interferon (GIF-D) -- an enzyme which stimulates the
body's immune system and is used clinically in the treatment of cancer.

*Human Serum Transferrin -- the major iron transport protein in human
serum. It transports iron from storage sites to hemoglobin synthesizing red
blood cells and also is a necessary component in media for cell growth.

*Porcine Pancreatic Elastase -- an enzyme associated with the
degratation of lung tissue in people suffering from emphysema. A better
understanding of the enzyme's structure will be useful in studying the
causes of this debilitating disease.

*Type IV Collagenase -- an enzyme obtained from snake venom
(haemmioragic), it is related to collagenase secreted by invasive cancer
cells.

*Canavalin -- the major storage protein of leguminous plants such as
beans and peas, and a major source of dietary protein for humans and
domestic animals.

*Malic Enzyme -- an enzyme isolated from nematodes. Characterizing
the structural differences between it and the mammalian version could to
the development of an anti-parasite drug.

*Anti-HPR Fab fragment/Fab -- the detailed structure would provide a
picture of an antibody binding site which recognizes a bacterial "foreign"
protein antigen. By learning what antibody binding sites look like, we may
better understand how antibodies function in the immune system.

*Factor D -- an enzyme necessary for activation of a part of the
immune system which plays an important role in host defense against
pathogens.

*Turkey/Quail Lysozyme -- Sugars are often found associated with
proteins, and these sugar/protein interactions are fundamental in all the
processes of living organisms. However, very little is known about these
interactions.

*Carboxyl Ester Hydrolase -- an enzyme which catalyzes the breakdown
of carboxylic acid esters like those found in fats. Understanding how this
enzyme functions will be valuable in learning how fats and related
molecules are made and metabolized.

Shortly after achieving orbit, a crewmember will combine each
of the protein solutions with other solutions containing a precipitation
agent to form small droplets on the ends of double-barreled syringes
positioned in small chambers. Water vapor will diffuse from each droplet
to a solution absorbed in a porous reservoir that lines each chamber.

The loss of water by this vapor diffusion process will produce
conditions in the droplets that cause protein crystals to grow. The
samples will be processed at 22 degrees C, as on STS-26 and STS-29.

Just prior to descent, the mission specialist will photograph the
droplets in the trays. Then all the droplets and any protein crystals
grown will be drawn back into the syringes. The syringes then will be
resealed for reentry. Upon landing, the hardware will be turned over to

the investigating team for analysis.

The PCG experiments are sponsored by NASA's Office of Commercial
Programs and the Microgravity Science and Applications Division with
management provided through Marshall Space Flight Center (MSFC),
Huntsville, Ala. Richard E. Valentine, is mission manager and Blair Herron
is PCG experiment manager for Marshall.

Dr. Charles E. Bugg, director of the Center for Macromolecular
Crystallography, a NASA-sponsored Center for the Commercial Development of
Space located at the University of Alabama-Birmingham (UAB), is lead
investigator for the PCG research team.

The STS-31 industry, university and government PCG research
investigators include DuPont de Nemours & Co.; U.S. Naval Research
Laboratory; BioCryst, Inc.; Schering Plough Corp.; Georgia Institute of
Technology; Vertex Pharmaceuticals; Texas A&M University; University of
California at Riverside; The Upjohn Co.; National Research Council of
Canada; UAB Center for Macromolecular Crystallography; Laboratoire de
Cristallographie et Cristallisation de Macromoles Biologiques-Faculte Nord,
Marseille, France; and Eastman Kodak Co.

INVESTIGATIONS INTO POLYMER MEMBRANE PROCESSING

The Investigations into Polymer Membrane Processing (IPMP) is a
middeck payload developed by the Battelle Advanced Materials Center for the
Commercial Development of Space (CCDS), Columbus, Ohio. Sponsored by NASA's
Office of Commercial Programs, the Battelle CCDS was formed in November
1985 to conduct research into commercially important advanced materials
such as polymers, catalysts, electronic materials and superconductors. The
IPMP marks the beginning of the center's work in microgravity polymer
membrane processing.

Polymer membranes have been used in the separations industry for many
years for such applications as desalination of water, filtration during the
processing of food products, atmospheric purification, medicinal
purification and dialysis of kidneys and blood.

One method of producing polymer membranes is evaporation casting. In
this process, a membrane is prepared by forming a mixed solution of polymer
and solvent into a thin layer -- the solution is then evaporated to
dryness. The polymer membrane is left with a certain degree of porosity
and can then be used for the applications described above.

Although polymer chemists do not fully understand the importance of
the evaporation step in the formation of thin-film membranes, a study has
demonstrated that convective flows during processing do, in fact, influence
the structure of the membrane. Convective flows are a natural result of the
effects of gravity on liquids or gases that are non-uniform in specific
density. The microgravity of space will permit researchers to study
polymer membrane casting in a convection-free environment.

The IPMP payload on STS-31 consists of two experimental units and
their contents. Each IPMP unit consists of two sample cylinders connected
to each other by a valve. The larger of the two cylinders is 8 inches long
and 4 in. in diameter, with the smaller cylinder measuring 4.5 by 2 in.
The overall dimensions of each IPMP unit are 18.6 by 3.5 by 4.41 in. The
total weight of the flight hardware (both units) is approximately 17
pounds.

Before launch the larger cylinder, sealed on one end, is evacuated
and sealed on the other end by closing the valve. The valve is then
secured to preclude accidental opening during ground processing activities.

A thin-film polymer membrane is swelled in a solvent solution. (In
this first flight experiment, the polymer -- polysulfone -- is swollen with
a mixture of dimethylacetamide and acetone.) The resultant swollen gel
(viscous fluid) is measured and inserted into a sample tube, which is
inserted into the smaller of the two cylinders. This cylinder is sealed at
ambient pressure (-14.7 psia) and attached to the other side of the valve.
The procedure is repeated for the second unit. Once Discovery's on-orbit
activities allow it, a crewmember will release and open the valve on each
unit. Opening the valve causes the solvents in the smaller cylinder to
flash- evaporate into the vacuum of the larger cylinder. The remaining
thin-film polymer membrane has a porosity related to the evaporation of the
solution. The system reaches an equilibrium state, which is maintained for
the remainder of the flight. The minimum duration needed for adequate
results is 24 hours.

The IPMP occupies the space of a single small stowage tray (one-half
of a middeck locker). The two units are positioned in foam inserts in the
stowage tray. The IPMP is self-contained and requires no power from the
Shuttle orbiter. Upon landing the IPMP will be returned to Battelle for
analysis.

Principal investigator for the IPMP is Dr. Vince McGinniss of
Battelle. Lisa A. McCauley, Associate Director of the Battelle CCDS, is
program manager.

ASCENT PARTICLE MONITOR

The Ascent Particle Monitor is an automatic system mounted in
Discovery's payload bay to measure particle contamination or particle
detachment during the immediate prelaunch period and during ascent.

The payload consists of a small box with a fixed door and a moving
door mounted in a clamshell arrangement atop an aluminum housing. Each
door contains six sample coupons.

The doors are closed together preflight to protect the coupons from
the environment. At a preselected time, the doors open exposing the
coupons for a selected period of time. They are then closed to seal the
coupons for later analysis. A motor/gearbox assembly, two battery packs
and launch detection and door opening circuitry are contained within the
aluminum housing.

RADIATION MONITORING EXPERIMENT

The Radiation Monitoring Experiment (RME) will record both the rate
and total dosage of all types of ionizing radiation (gamma ray, neutron and
proton radiation). The experiment consists of a single handheld instrument
with replaceable memory modules. It contains a liquid crystal display for
realtime data display and a keyboard for controlling its functions.

The experiment is self-contained with two zinc-air and five AA
batteries contained in each memory module and two zinc-air batteries in the
main module. RME-III will be activated as soon as possible after orbit is
achieved and will be programmed to operate throughout the entire mission.
A crew member will enter the correct mission elapsed time upon activation
and change the memory module every 2 days. All data stored in the memory
modules will be analyzed at the completion of the mission.

Student Science Investigation Project

"Investigation of Arc and Ion Behavior in Microgravity"

This SSIP experiment, selected in 1982, was proposed by Gregory S.
Peterson, formerly of Box Elder High School, Brigham City, Utah. The
experiment is designed to study the effect of weightlessness on electrical
arcs.

In a normal Earth environment when electricity moves through the air
between two points, air molecules become charged and form an ion path. This
ion path is electrically more conductive than the surrounding air.
Convective currents caused by the heating of the air around the arc tend to
force the arc to rise, known as the "Jacob's ladder" effect.

In a weightless environment, convection currents cannot be created in
this way, so the arc will behave differently. It is postulated that the
arc shape will depend on things such as interaction between the ions, the
magnetic field generated by the arc, and others. These things are not
observable on Earth because the effect of convection is so much stronger
than any of the other forces.

To observe the effects of free fall on an arc and to study the effects
of a magnetic field on an arc without convection, Peterson's experimental
apparatus consists of a sealed aluminum arc chamber box within a sealed
aluminum outer box. Both boxes have a window in which a wire screen is
embedded to prevent the escape of electromagnetic interference while
allowing viewing and photography. Both boxes are filled with a mixture of
67% argon and 33% nitrogen to prevent the formation of ozone. Experiment
results could have possible applications to materials processing in space.

Peterson is now a senior studying chemistry and biology at Utah State
University. His teacher advisor is Darrel Turner, formerly with Box Elder
High School. The experiment was sponsored by Thiokol Corp., with the
science advice of Val King, Space Dynamics Laboratories.

IMAX

The IMAX project is a collaboration between NASA and the Smithsonian
Institution's National Air and Space Museum to document significant space
activities using the IMAX film medium. This system, developed by IMAX
Systems Corp., Toronto, Canada, uses specially designed 70mm film cameras
and projectors to record and display very high definition large- screen
pictures.

During Shuttle Mission STS-31, an IMAX Cargo Bay Camera (ICBC) will be
carried in the payload bay of Discovery and used to document activities
associated with the deployment of the Hubble Space Telescope. The camera is
mounted in the in a pressure-sealed container with a viewing window. The
window has a sliding door which opens when the camera is in operation. The
camera is controlled from the aft-flight deck, exposing the film through a
30mm fisheye lens.

A second IMAX camera will be flown in the mid-deck of the orbiter and
will be used by the crew to collect additional material for upcoming IMAX
productions.

Imax cameras previously have flown on Space Shuttle missions 41-C, 41-
D and 41-G to document crew operations in the payload bay and the orbiter's
middeck and flight deck along with spectacular views of Earth. Film from
those missions form the basis for the IMAX production, The Dream is Alive.

The IMAX camera flew on STS-29 in March 1989, STS-34 in October 1989
and most recently STS-32 in January 1990. During those missions, the
camera was used to gather material for an upcoming IMAX production entitled
The Blue Planet.


CREW BIOGRAPHIES

Loren J. Shriver, 46, Col. USAF, will serve as Commander. Selected as
an astronaut in 1978, he considers Paton, Iowa, to be his hometown and will
be making his second Shuttle flight.

Shriver was Pilot for STS-51C, the eleventh shuttle flight and a DOD-
dedicated mission, launched on Jan. 24, 1985. The five-member crew spent 3
days in orbit aboard Challenger.

Shriver graduated from Paton Consolidated High School in 1962 and
received a bachelor of science degree in aeronautical engineering from the
United States Air Force Academy in 1967. He received a master of science
degree in aeronautical engineering from Purdue University in 1968.

Commissioned by the Air Force in 1967, Shriver served as a T-38
academic instructor pilot at Vance Air Force Base, Okla., from 1969-1973.
He completed F-4 combat crew training in 1973 and completed a 1-year
overseas assignment in Thailand in 1974. He attended the USAF Test Pilot
School in 1975 and, from 1976 until his selection by NASA, served as a test
pilot with the F-15 Joint Test Force at Edwards Air Force Base, Calif.
Shriver has logged more than 5,000 hours in jet aircraft and flown 30
different types of single- and multi-engine aircraft.

Charles F. Bolden Jr., 44, Col. USMC, will serve as Pilot. Selected as
an astronaut in 1980, he was born in Columbia, S.C., and will be making his
second Shuttle flight.

Bolden was Pilot for STS-61C, a 6-day flight of Columbia launched Jan.
12, 1986. The crew deployed a SATCOM KU satellite and conducted experiments
in astrophysics and materials processing. The flight culminated in a night
landing at Edwards.

Bolden graduated from C.A. Johnson High School in Columbia in 1964. He
received a bachelor of science degree in electrical science from the United
States Naval Academy in 1968 and a master of science from the University of
Southern California in 1978.

Bolden accepted a commission in the Marine Corps in 1968 and was
designated a naval aviator in 1970. From 1972-1973, he flew more than 100
sorties in Vietnam while stationed in Thailand. In 1979, he graduated from
the Naval Test Pilot School and was assigned to the Naval Air Test Center's
systems engineering and strike aircraft test directorates, where he worked
until his selection by NASA. Bolden has logged more than 4,800 hours
flying time.

Bruce McCandless II, 53, Capt. USN, will serve as Mission Specialist-1
(MS-1). Selected as an astronaut in 1966, he was born in Boston, Mass., and
will be making his second Shuttle flight.

McCandless was a Mission Specialist aboard Challenger on STS-41B, the
tenth Shuttle flight. During the 8-day flight, the crew deployed two
Hughes 376 communications satellites and McCandless completed two
spacewalks, taking the shuttle's manned maneuvering unit (MMU) on its
maiden voyage. The flight ended with the first landing at Kennedy Space
Center.

McCandless graduated from Woodrow Wilson Senior High School, Long
Beach, Calif., and received a bachelor of science degree from the U.S.
Naval Academy in 1958. He received a master of science degree in electrical
engineering from Stanford University in 1965 and a master's degree in
business administration from the University of Houston-Clear Lake in 1987.
Designated a naval aviator in 1960, he has logged more than 5,200 hours of
flying time, 5,000 of them in jet aircraft.

At NASA, McCandless was a member of the astronaut support crew for the
Apollo 14 mission; backup pilot of the first manned Skylab mission; and
worked with development of astronaut maneuvering units for more than 10
years.

Steven A. Hawley, 39, will be Mission Specialist-2 (MS-2). Selected as
an astronaut in 1978, Hawley considers Salina, Kansas, to be his hometown
and will be making his third Shuttle flight.

Hawley first flew on STS-41D, the twelfth Shuttle flight and the
maiden flight of Discovery, launched Aug. 30, 1984. During the 7-day
flight, the six- member crew deployed the SBS-D, SYNCOM IV-2 and TELSTAR
satellites. His second flight was aboard Columbia on STS-61C, on which
fellow STS-31 crew member Bolden served as pilot.

Hawley graduated from Salina Central High School in 1969 and received
bachelor of arts degrees in physics and astronomy from University of Kansas
in 1973. He received a doctor of philosophy in astronomy and astrophysics
from the University of California in 1977. At NASA, Hawley now serves as
deputy chief of the Astronaut Office.

Kathryn D. Sullivan, 39, will serve as Mission Specialist-3 (MS-3).
Selected as an astronaut in 1978, she considers Woodland Hills, Calif., to
be her hometown and will be making her second Shuttle flight.

Sullivan flew on STS-41G, the thirteenth Shuttle flight, launched on
Oct. 5, 1984. During the 8-day flight, the seven-member crew deployed
Earth Radiation Budget satellite and conducted observations of Earth using
the OSTA-3 flight. Sullivan conducted a 3.5-hour spacewalk to demonstrate
the feasibility of refueling satellites in orbit, making her the first U.S.
woman to walk in space.

Sullivan graduated from Taft High School in Woodland Hills in 1969 and
received a bachelor of science degree in Earth sciences from the University
of California at Santa Cruz in 1973. She received a doctorate in geology
from Dalhousie University, Halifax, Nova Scotia, in 1978. At NASA,
Sullivan's research interests have focused on remote sensing and planetary
geology, and she made several flights in the WB-57F high-altitude research
plane participating in several remote sensing projects in Alaska in 1978.
She was a co-investigator on the Shuttle Imaging Radar-B experiment which
flew on STS-41G.

Sullivan is an oceanography officer in the U.S. Naval Reserve and has
attained the rank of Lt. Cmdr. She also is a private pilot, rated in
powered and glider aircraft.

MISSION MANAGEMENT FOR HUBBLE SPACE TELESCOPE LAUNCH

Office of Space Science and Applications

Dr. Lennard A. Fisk - Associate Administrator
Alphonso V. Diaz - Deputy Associate Administrator
Dr. Charles J. Pellerin, Jr. - Director, Astrophysics Division
Douglas R. Broome - Chief, Observatories Development Branch
HST Program Manager
David J. Pine - HST Deputy Program Manager
Dr. Edward J. Weiler - Chief, UV/Visible Astrophysics Branch
HST Program Scientist
Dr. Geoffery Clayton - HST Deputy Program Scientist
Ralph Weeks - Observatories Servicing Program Manager

Office of Space Flight

Dr. William B. Lenoir - Associate Administrator
Joseph B. Mahon - Deputy Associate Administrator (Flight Systems)
Robert L. Crippen - Director Space Shuttle Program
Leonard E. Nicholson - Deputy Director Space Shuttle Program

Office of Space Operations

Charles T. Force - Associate Administrator
Eugene Ferrick - Director, Tracking & Data Relay Satellite Systems Division
Robert M. Hornstein - Director, Ground Networks Division

Johnson Space Center

Aaron Cohen - Director
Eugene F. Kranz - Director, Mission Operations
William D. Reeves - STS-31 Flight Director
Nellie N. Carr - STS-31 Payload Officer
Richard M. Swalin - HST Payload Integration Manager

Marshall Space Flight Center

Thomas J. Lee - Director
Fred S. Wojtalik - HST Project Manager
Jean R. Olivier - HST Deputy Project Manager
Michael M. Harrington - HST Director of Orbital Verification
William E. Taylor - HST Systems Engineering Manager
Max E. Rosenthal - HST Optical Telescope Assembly and
Maintenance & Refurbishment Manager
John H. Harlow - HST Support Systems Manager
Dr. Frank Six - HST Deputy Project Scientist

Goddard Space Flight Center

Dr. John W. Townsend, Jr. - Director
Peter T. Burr - Director of Flight Projects
James W. Moore - GSFC HST Project Manager
Dr. John H. Campbell - GSFC HST Deputy Project Manager
Joseph E. Ryan - HST Mission Operations Manager
Dr. Albert Boggess - HST Project Scientist
Dr. Keith J. Kalinowski - HST Director of Science Verification
Dale L. Fahnestock - Director of Mission Operations and
Data Systems Directorate

Kennedy Space Center

Forrest S. McCartney - Director
Jay Honeycutt - Director, Shuttle Management & Operations
John T. Conway - Director, Payload Management & Operations
Joanne H. Morgan - Director, Payload Project Management

European Space Agency

Robin Lawrance - ESA Project Manager
Dr. Peter Jakobsen - FOC Project Scientist
Dr. Duccio Macchetto - Chairman FOC TDT