Our Solar System/Our Solar System.iso/shuttle/sts46/sts46.kit

Text File | 1992-07-21 | 111.0 KB | 2,674 lines

REVISED STS-46 PRESS KIT




             NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

                       SPACE SHUTTLE MISSION

                         STS-46 PRESS KITT





                             JULY 1992







PUBLIC AFFAIRS CONTACTS

NASA Headquarters

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


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


Office of Commercial Programs
Barbara Selby


Office of Aeronautics and Space Technology
Drucella Andersen/Les Dorr


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



Ames Research Center
Jane Hutchison


Langley Research Center
Jean Drummond Clough

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


Goddard Space Flight Center           Marshall Space Flight Center
Dolores Beasley                       Mike Simmons


Jet Propulsion Laboratory             Stennis Space Center
James Wilson                          Myron Webb


Johnson Space Center                   Wallops Flight Center
James Hartsfield                       Keith Koehler


Kennedy Space Center
Lisa Malone





CONTENTS

General Release                                1

Media Services Information                     4

Quick-Look-Facts                               5

Summary of Major Activities                    6

Payload and Vehicle Weights                    7

Trajectory Sequence of Events                  8

Space Shuttle Abort Modes                      9

Prelaunch Processing                          10

Tethered Satellite System (TSS-1)             12

European Retrievable Carrier (EURECA)         34

Evaluation of Oxygen Interaction with Materials (EOIM)/
Two Phase Mounting Plate Experiment (TEMP)    47

Consortium for Materials Development
in Space (Complex Autonomous Payload)          49

Limited Duration Space Environment
Candidate Materials Exposure (LDCE)            50

Pituitary Growth Hormone Cell Function (PHCF)  52

IMAX Cargo Bay Camera (ICBC)                   52

Air Force Maui Optical Station (AMOS)          55

Ultraviolet Plume Imager (UVPI)                55

STS-46 Crew Biographies                        55

Mission Management for STS-46                  58

Previous Shuttle Flights                       60

Upcoming Space Shuttle Flights                 61



49TH SHUTTLE FLIGHT TO TEST FEASIBILITY OF TETHERED SATELLITE

Release:  92-95


     Highlighting Shuttle mission STS-46 will be experiments
involving a 12.5-mile-long tether connecting a satellite to
the orbiter Atlantis, to demonstrate the feasibility of the
technology for a variety of uses ranging from generating
electrical power to researching the upper atmosphere.

     During the mission the crew also will deploy the
European Retrievable Carrier (EURECA-1) platform, which
contains a series of experiments dealing with materials
sciences, life sciences and radiobiology.  The platform will
remain in orbit for about 9 months before being retrieved
during a later Shuttle mission.

     "First and foremost, this is a mission of discovery,"
Thomas Stuart, Tethered Satellite System Program Manager
said.

     "It's the first time we've ever deployed a satellite on
a long tether in space.  This system is at the leading edge
of scientific discovery and will give us a glimpse of space
technologies of the future," he said.

     STS-46 is scheduled for launch in late July.  It will be
the 12th flight for Atlantis, and is scheduled to last 6
days, 22 hours and 11 minutes, with a planned landing at
Kennedy Space Center, Fla.


TETHERED SATELLITE SYSTEM

     The Tethered Satellite System-1 (TSS-1) -- a joint
project of the United States and Italy under an agreement
signed in 1984 -- consists of a satellite, a 1/10th inch
diameter tether and a deployer in the Shuttle's cargo bay.

     The 1,139 pound satellite was developed by the Italian
Space Agency (ASI) and the tether and deployer system were
developed by the U.S.  The 12 main experiments were selected
jointly by NASA and ASI.

     "During this mission we're going to learn a great deal
about how to safely operate a tether system," Stuart said.
"We're going to demonstrate the feasibility of usinf a tether
to generate electricity, as a propulsion system to power
spacecraft and for studying the Earth's magnetic field and
ionosphere."

     When the tether is fully extended to its 12 1/2 mile
length, the combination of the orbiter, tether and satellite
combined will be the longest structure ever flown in space.


EURECA

     The crew will deploy the European Space Agency's (ESA)
EURECA-1, which will then ascend to its operational orbit of
515 km using its own propulsion system.  After 9 months it
will be moved to a lower orbit for retrieval by another
Shuttle in late April 1993.  After its return to Earth it
will be refurbished and equipped for its next mission.

     Aboard EURECA-1 are 15 experiments devoted to
researching the fields of material science, life sciences and
radiobiology, all of which require a controlled microgravity
environment.  The experiments include:

     O protein crystallization
     O biological effects of space radiation
     O measurements of fluids' critical points
         in microgravity
     O measurements of solar irradiation
     O solar/terrestrial relationship in aeronomy
          and climatology
     O electric propulsion in space

     Scientists participating in the investigations are from
Belgium, Germany, Denmark, France, Italy, United Kingdom and
The Netherlands.

     EURECA-1 was built by the ESA and designed to be
maintained during its long-term mission by ground controllers
at ESA's Space Operations Centre (ESOC), Darmstadt, Germany.


ADDITIONAL PAYLOADS

     Additional payloads carried in Atlantis' cargo bay
include the:

     O Evaluation of Oxygen Interaction with Materials III
(EOIM) experiment to study how oxygen molecules in low-Earth
orbit affect materials that will be used to construct Space
Station Freedom;

     O Thermal Energy Management (TEMP 2A) experiment to test
a new cooling method that may be used in future spacecraft;

     O Consortium for Material Development in Space Complex
Autonomous Payload experiment to study materials processing;

     O Limited Duration Space Environment Candidate Materials
Exposure experiments will explore materials processing
methods in weightlessness;

     O An IMAX camera will be in the payload bay to film
various aspects of the mission for later IMAX productions.


     Atlantis will be commanded by USAF Col. Loren Shriver,
making his third Shuttle flight.  Marine Corps Major Andy
Allen will serve as pilot, making his first flight.  Mission
specialists will include Claude Nicollier, a European Space
Agency astronaut making his first Shuttle flight; Marsha
Ivins, making her second Shuttle flight; Jeff Hoffman, making
his third space flight; and Franklin Chang-Diaz, making his
third space flight.  Franco Malerba from the Italian Space
Agency will be the payload specialist aboard Atlantis.

                            -end-


MEDIA SERVICES INFORMATION


NASA Select Television Transmission

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

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

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

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

     A mission press briefing schedule will be issued prior
to launch.  During the mission, change-of-shift briefings by
the off-going flight director and the science team will occur
at least once per day.  The updated NASA Select television
schedule will indicate when mission briefings are planned.



STS-46 QUICK LOOK

Launch Date/Site:     July 21, 1992 - Kennedy Space Center,
                                        Fla.,
                      Pad 39B
Launch Window:        9:48 a.m. - 12:18 p.m. EDT
Orbiter:              Atlantis (OV-104)
Orbit:                230 n.m. x 230 n.m. (EURECA deploy)
                      160 n.m. x 160 n.m. (TSS operations)
                      128 n.m. x 128 n.m. (EOIM operations)
Landing Date/Time:     7:57 a.m. EDT July 28, 1992
Primary Landing Site:  Kennedy Space Center, Fla.
Abort Landing Sites:   Return to Launch Site - Kennedy Space
                                                Center, Fla.
                       Transoceanic Abort Landing - Banjul,
                       The Gambia
                       Alternates - Ben Guerir, Morocco;
                       Moron, Spain
                       Abort Once Around - Edwards Air Force
                       Base, Calif.
Crew:                  Loren Shriver, Commander
                       Andy Allen, Pilot
                       Claude Nicollier, Mission Specialist 1
                       Marsha Ivins, Mission Specialist 2
                       Jeff Hoffman, Mission Specialist 3
                       Franklin Chang-Diaz, Mission
                         Specialist 4
                       Franco Malerba, Payload Specialist 1
Operational shifts:    Red team -- Ivins, Hoffman, Chang-Diaz
                       Blue team -- Nicollier, Allen, Malerba

Cargo Bay Payloads:  TSS-1 (Tethered Satellite System-1)
                     EURECA-1L (European Retrievable Carrier-
                                  1L)
                     EOIM-III/TEMP 2A (Evaluation of Oxygen
                     Integration with Materials/Thermal
                       Management  Processes)
                     CONCAP II (Consortium for Materials
                     Development in Space Complex Autonomous
                     Payload)
                     CONCAP III
                     ICBC (IMAX Cargo Bay Camera)
                     LDCE (Limited Duration Space Environment
                     Candidate Materials Exposure)

Middeck Payloads:    AMOS (Air Force Maui Optical Site)
                     PHCF (Pituitary Growth Hormone Cell
Function)
                     UVPI (Ultraviolet Plume Instrument)



STS-46 SUMMARY OF MAJOR ACTIVITIES


Blue Team Flight Day One:      Red Team Flight Day One
                               Launch
                             Orbit insertion (230 x 230 n.m.)
                               TSS activation
                               RMS checkout
                               TSS deployer checkout
                               EOIM/TEMP-2A activation

Blue Flight Day Two:           Red Flight Day Two:
EURECA deploy                  TEMP-2A operations
EURECA stationkeeping          Tether Optical Phenomenon
(TOP)
                                       checkout

Blue Flight Day Three:         Red Flight Day Three:
TOP checkout                   TSS checkout/in-bay operations
Supply water dump nozzle DTO
TEMP-2A operations
OMS-3 burn
OMS-4 burn (160 x 160 n.m.)

Blue Flight Day Four:           Red Flight Day Four:
TSS in-bay operations           TSS deploy
                                TEMP-2A operations

Blue Flight Day Five:           Red Flight Day Five:
TSS on station 1 (12.5 miles)   TSS retrieval to 1.5 miles
                                TSS final retrieval
                                TSS dock

Blue Flight Day Six:            Red Flight Day Six:
TSS safing                      EOIM/TEMP-2A operations
TSS in-bay operations
OMS-5 burn
OMS-6 burn (128 x 128 nm)

Blue Flight Day Seven:          Red Flight Day Seven:
TSS science deactivation        EOIM/TEMP-2A operations
EOIM/TEMP-2A operations         Flight Control Systems
checkout
                                Reaction Control System
                                  hot-fire

Blue Flight Day Eight:           Red Flight Day Eight:
                                 Cabin stow
                                 Deorbit preparations
                                 Entry and landing


STS-46 VEHICLE AND PAYLOAD WEIGHTS


                                                       Pounds

Orbiter (Atlantis) empty, and 3 SSMEs                 151,377

Tethered Satellite -- pallet, support equipment        10,567

Tethered Satellite -- satellite, tether                 1,200

European Retrievable Carrier                            9,901

EURECA Support Equipment                                  414

Evaluation of Oxygen Interaction with Materials         2,485

CONCAP-II                                                 590

CONCAP-III                                                368

LDCE                                                    1,125

PHDF                                                       69

Detailed Supplementary Objectives                          56

Detailed Test Objectives                                   42

Total Vehicle at SRB Ignition                       4,522,270

Orbiter Landing Weight                                208,721


STS-46 Cargo Configuration


STS-46 TRAJECTORY SEQUENCE OF EVENTS

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

Launch                  00/00:00:00

Begin Roll Maneuver     00/00:00:10            189          .16       797

End Roll Maneuver       00/00:00:15            325           29     2,260

SSME Throttle Down to 80% 00/00:00:26          620          .55     6,937

SSME Throttle Down to 67%  00/00:00:53       1,236        1.20     28,748

SSME Throttle Up to 104%  00/00:01:02        1,481        1.52     37,307

Maximum Dynamic Press     00/00:01:04       1,548         1.61     41,635
(Max Q)

SRB Separation            00/00:02:04       4,221         4.04    152,519

Main Engine Cutoff (MECO)  00/00:08:29     24,625        22.74    364,351

Zero Thrust                00/00:08:35     24,624       N/A       363,730

ET Separation              00/00:08:48

OMS-2 Burn                 00/00:41:24

Landing                    06/22:11:00


Apogee, Perigee at MECO:          226 x 32 nautical miles
Apogee, Perigee post-OMS 2:       230 x 230 nautical miles


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

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

    * Return-To-Launch-Site (RTLS) -- Early shutdown of one
or more engines, 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-46 contingency landing sites are Edwards Air Force
Base, the Kennedy Space Center, White Sands Space Harbor,
Banjul, Ben Guerir and Moron.


STS-46 PRE-LAUNCH PROCESSING

     KSC's processing team began readying the orbiter
Atlantis for its 12th flight into space following its STS-45
flight that ended with a landing at KSC on April 2.  Atlantis
was in the Orbiter Processing Facility (OPF) from April 2 to
June 4, undergoing post-flight inspections and pre-flight
testing and inspections.  While in the OPF, technicians
installed the three main engines.  Engine 2024 is in the No.
1 position, engine 2012 is in the No. 2 position and engine
2028 is in the No. 3 position.

     The remote manipulator system was installed on Apr. 28.
Members of the STS-46 flight crew participated in the Crew
Equipment Interface Test on May 16.

     Atlantis was towed from the Orbiter Processing Facility
(OPF) on June 4 to the Vehicle Assembly Building where it was
mated to its external tank and solid rocket boosters.
Rollout to Launch Pad 39-B occurred on June 11, 1992.  On
June 15-16, the Terminal Countdown Demonstration Test with
the STS-46 flight crew was conducted.

     The Tethered Satellite System (TSS) was processed for
flight in the Operations and Checkout Building high bay and
the EURECA payload was processed at the commercial Astrotech
facility in Titusville, Fla.  The two primary payloads were
installed in the payload canister at the Vertical Processing
Facility before they were transferred to the launch pad.

     Payload installation into Atlantis' payload bay was
accomplished July 8.  Several interface verification tests
were scheduled between the orbiter and the payload elements.
A standard 43-hour launch countdown is scheduled to begin 3
days prior to launch.  During the countdown, the orbiter's
fuel cell storage tanks will be loaded with fuel and oxidizer
and all orbiter systems will be prepared for flight.

     About 9 hours before launch, the external tank will be
filled with its flight load of a half million gallons of
liquid oxygen and liquid hydrogen propellants.  About 2 and
one-half hours before liftoff, the flight crew will begin
taking their assigned seats in the crew cabin.

     Atlantis's end-of-mission landing is planned at Kennedy
Space Center. Several hours after landing, the vehicle will
be towed to the Vehicle Assembly Building for a few weeks
until an OPF bay becomes available. Atlantis will be taken
out of flight status for several months for a planned
modification period.  Atlantis' systems will be inspected and
improved to bring the orbiter up to par with the rest of the
Shuttle fleet.

     Atlantis's next flight, STS-57, is planned next year
with the first flight of the Spacehab payload and the
retrieval of the EURECA payload deployed on the STS-46
mission.


TETHERED  SATELLITE  SYSTEM (TSS-1)

     An exciting new capability for probing the space
environment and conducting experiments will be demonstrated
for the first time when the NASA/Italian Space Agency
Tethered Satellite System (TSS-1) is deployed during the STS-
46 Space Shuttle flight.

     The Tethered Satellite System is made up of a satellite
attached to the Shuttle orbiter by a super strong cord that
will be reeled into space from the Shuttle's cargo bay.  When
the satellite on its cord, or tether, is deployed to about 12
miles above the orbiter, TSS-1 will be the longest structure
ever flown in space.

     For the TSS-1 mission, the tether -- which looks like a
12-mile-long white bootlace -- will have electrically-
conducting metal strands in its core.

     The conducting tether will generate electrical currents
at a high voltage by the same basic principle as a standard
electrical generator -- by converting mechanical energy (the
Shuttle's more than 17,000-mile-an-hour orbital motion) into
electrical energy by passing a conductor through a magnetic
field (the Earth's magnetic field lines).

     TSS-1 scientific instruments, mounted in the Shuttle
cargo bay, the middeck and on the satellite, will allow
scientists to examine the electrodynamics of the conducting
tether system, as well as clarify their understanding of
physical processes in the ionized plasma of the near-Earth
space environment.

     The TSS-1 mission will be the first step toward several
potential future uses for tethers in space now being
evaluated by scientists and engineers.  One possible
application is using long conducting tethers to generate
electrical power for Space Station Freedom or other orbiting
bodies.

     Conversely, by expending electrical power to reverse the
current flow into a tether, the system could be placed in an
"electric motor" mode to generate thrust for orbit
maintenance.  Tethers also may be used to raise or lower
spacecraft orbits.  This could be achieved by releasing a
tethered body from a primary spacecraft, thereby transferring
momentum (and imparting motion) to the spacecraft.  Another
potential application is the creation of artificial gravity
by rotating two or more masses on a tether, much like a set
of bolas.

     Downward deployment (toward Earth) could place a
satellite in regions of the atmosphere that have been
difficult to study because they lie above the range of high-
altitude balloons and below the minimum altitude of free-
flying satellites.  Deploying a tethered satellite downward
from the Shuttle also could make possible aerodynamic and
wind tunnel type testing in the region 50 to 75 nautical
miles above the Earth.


Mission Objectives

     Space-based tethers have been studied theoretically
since early in this century.  The first practical application
of a shuttle-based tether was developed by Dr. Mario Grossi,
Smithsonian Institutin, in the early 1970s.  Professor
Guiseppe Colombo, University of Padova, Italy, subsequently
proved the dynamic feasibility of the tether concept and
suggested various uses.  More recently, the projected
performance of such systems has been modeled extensively on
computers.

     In 1984, the growing interest in tethered system
experiments resulted in the signing of an agreement between
NASA and the Italian Space Agency (Agenzia Spaziale Italiana
- ASI) to jointly pursue the definition and development of a
Tethered Satellite System to fly aboard the Space Shuttle.
Scientific investigations (including hardware experiments)
were selected in 1985 in response to a joint NASA/ASI
announcement of opportunity.

     The TSS-1 mission will be the first time such a large,
electrodynamic tethered system has ever been flown.  In many
respects, the mission is like the first test flight of a new
airplane:  the lessons learned will improve both scientific
theory and operations for future tether missions.

     The mission objectives are to evaluate the capability
for safely deploying, controlling and retrieving a tethered
satellite; to validate predictions of the dynamic forces at
work in a tethered satellite system; to conduct exploratory
electrodynamic science investigations; and to demonstrate the
capability of the system to serve as a facility for research
in geophysical and space physics.

     Since the dynamics of the Tethered Satellite System are
complex and only can be tested fully in orbit, it is
impossible to predict before the mission exactly how the
system will perform in the space environment.  In particular,
retrieval and recapture present the greatest uncertainties.

     Though tether system dynamics have been extensively
tested and simulated, it could be that actual dynamics will
differ somewhat from predictions.  The complexity of a widely
separated, multi-component system and the forces created by
the flow of current through the system are other variables
that will affect the system's performance.

Responsibilities

     Responsibility for Tethered Satellite System activities
within NASA is divided between the Marshall Space Flight
Center, Huntsville, Ala., and the Johnson Space Center,
Houston.  Marshall has the development and integration
responsibility.  Marshall also is responsible for developing
and executing the TSS-1 science mission, and science teams
for each of the 12 experiments work under that center's
direction.  During the mission, Johnson will be responsible
for the operation of the TSS-1 payload.  This includes
deployment and retrieval of the satellite by the crew as well
as controlling the satellite's motion in orbit and monitoring
the state of the

       Satellite (stowed for launch) and Deployer on Carriers


Spacelab pallet, the deployer and the satellite.  Marshall
will furnish real-time engineering support for the TSS-1
system components and tether dynamics.  The ASI
responsibility for the TSS system is the development of the
tethered satellite, the Italian onboard experiments and the
Core equipment.  In addition, ASI is providing satellite/Core
equipment engineering support during the mission.  All remote
commanding of science instruments aboard the satellite and
deployer will be executed by a Marshall payload operations
control cadre stationed at Johnson for the mission.

Tethered Satellite System Hardware

     The Tethered Satellite System has five major components:
the deployer system, the tether, the satellite, the carriers
on which the system is mounted and the science instruments.
Under the 1984 memorandum of understanding, the Italian Space
Agency agreed to provide the satellite and NASA agreed to
furnish the deployer system and tether.  The carriers are
specially adapted Spacelab equipment, and the science
instruments were developed by various universities,
government agencies and companies in the United States and
Italy.

Carriers

     TSS-1 hardware rides on two carriers in the Shuttle
cargo bay.  The deployer is mounted on a Spacelab Enhanced
Multiplexer-Demultiplexer pallet, a general-purpose
unpressurized platform equipped to provide structural support
to the deployer, as well as temperature control, power
distribution and command and data transmission capabilities.
The second carrier is the Mission Peculiar Equipment Support
Structure, an inverted A-frame truss located immediately aft
of the enhanced pallet.  The support structure, also
Spacelab-provided, holds science support equipment and two of
the TSS-1 science experiments.

Deployer

     The deployer system includes the structure supporting
the satellite, the deployment boom, which initially lifts the
satellite away from the orbiter, the tether reel, a system
that distributes power to the satellite before deployment and
a data acquisition and control assembly.

     Cables woven through the structure provide power and
data links to the satellite until it is readied for release.
When the cables are disconnected after checkout, the
satellite operates on its internal battery power.

     The boom, with the satellite resting atop it, is housed
in a canister in the lower section of the satellite support
structure.  As deployment begins, the boom will unfold and
extend slowly out of the turning canister, like a bolt being
forced upward by a rotating nut.  As the upward part of the
canister rotates, horizontal cross members (fiberglass
battens similar to those that give strength to sails) are
unfolded from their bent-in-half positions to hold the
vertical members (longerons) erect.  Additional strength is
provided by diagonal tension cables.  The process is reversed
for retrieval.  When it is fully extended, the 40-foot boom
resembles a short broadcasting tower.

          Orbiter with deployed tether and satellite


Tether cutaway

     The tether reel mechanism regulates the tether's length,
tension and rate of deployment -- critical factors for tether
control.  Designed to hold up to 68 miles of tether, the reel
is 3.3 feet in diameter and 3.9 feet long.  The reel is
equipped with a "level-wind" mechanism to assure uniform
winding on the reel, a brake assembly for control of the
tether and a drive motor.  The mechanism is capable of
letting out the tether at up to about 10 miles per hour.
However, for the TSS-1 mission, the tether will be released
at a much slower rate.

Tether

     The tether's length and electrical properties affect all
aspects of tethered operations.  For the TSS-1 mission, the
tether will be reeled out to an altitude about 12 miles above
the Shuttle, making the TSS-1/orbiter combination 100 times
longer than any previous spacecraft.  It will create a large
current system in the ionosphere, similar to natural currents
in the Earth's polar regions associated with the aurora
borealis.  When the tether's current is pulsed by electron
accelerators, it becomes the longest and lowest frequency
antenna ever placed in orbit.  Also, for the first time,
scientists can measure the level of charge or electric
potential acquired by a spacecraft as a result of its motion
through the Earth's magnetic field lines.  All these
capabilities are directly related to the structure of the
bootlace-thick tether, a conducting cord designed to anchor a
satellite miles above the orbiter.

     The TSS-1 tether is 13.7 miles long.  When deployed, it
is expected to develop a 5,000-volt electrical potential and
carry a maximum current of 1 ampere.  At its center is the
conductor, a 10-strand copper bundle wrapped around a Nomex
(nylon fiber) core.  The wire is insulated with a layer of
Teflon, then strength is provided with a layer of braided
Kevlar -- a tough, light synthetic fiber also used for making
bulletproof vests.  An outer braid of Nomex protects the
tether from atomic oxygen.  The cable is about 0.1 inch in
diameter.

Satellite

     Developed by the Italian Space Agency, the spherical
satellite is a little more than 5 feet in diameter and is
latched atop the deployer's satellite support structure.  The
six latches are released when boom extension is initiated.
After the satellite is extended some 40 feet above the
orbiter atop the boom, tether unreeling will begin.

     The satellite is divided into two hemispheres and a
centered propulsion module.  The payload module (the upper
half of the sphere opposite the tether) houses satellite-
based science instruments.  Support systems for power
distribution, data handling, telemetry and navigational
equipment are housed in the service module or lower half.
Eight aluminum-alloy panels, covered with electrically
conductive paint, developed at the Marshall Space Flight
Center, form the outer skin of the satellite.  Doors in the
panels provide access for servicing batteries; windows for
sun, Earth and charged-particle sensors; and connectors for
cables from the deployer.

     A fixed boom for mounting science instruments extends
some 39 inches from the equator of the satellite sphere.  A
short mast opposite the boom carries an S-band antenna for
sending data and receiving commands.  For the TSS-1 mission,
the satellite is outfitted with two additional instrument-
mounting booms on opposite sides of the upper sphere.  The
booms may be extended up to 8 feet from the body of the
satellite, allowing instruments to sample the surrounding
environment, then be retrieved inside the payload module
before the satellite is reeled back to the Shuttle.

     Attitude of the tethered satellite is controlled by its
auxiliary propulsion module, while the satellite motion is
controlled by the deployer's tether reel and motor.  The
module also initiates, maintains and controls satellite spin
at up to 0.7 revolution per minute on command from the
Shuttle.  One set of thrusters near the tether attachment can
provide extra tension on the tether, another can be used to
reduce or eliminate pendulum-type motions in the satellite,
and a third will be used to spin and de-spin the satellite.
A pressurized tank containing gaseous nitrogen for the
thrusters is located in the center of the sphere.


                  Satellite with booms extended

TSS Spacecraft


TETHERED SATELLITE SYSTEM-1 FLIGHT OPERATIONS

     The responsibility for flying the tethered satellite,
controlling the stability of the satellite, tether and
Atlantis, lies with the flight controllers in the Mission
Control Center at the Johnson Space Center, Houston.

     The primary flight control positions contributing to the
flight of the Tethered Satellite System (TSS) are the
Guidance and Procedures (GPO) area and the Payloads area.
GPO officers will oversee the dynamic phases of deployment
and retrieval of the satellite and are responsible for
determining the correct course of action to manage any tether
dynamics.  To compute corrective actions, the GPO officers
will combine data from their workstations with inputs from
several investigative teams.

     The Payloads area will oversee control of the satellite
systems, the operation of the tether deployer and all other
TSS systems.  Payloads also serves as the liaison between
Mission Control Center and the science investigators, sending
all real-time commands for science operations to the
satellite.  Atlantis' crew will control the deployer reel and
the satellite thrusters from onboard the spacecraft.

Deploy Operations

     The satellite will be deployed from Atlantis when the
cargo bay is facing away from Earth, with the tail slanted
upward and nose pitched down.  A 39-foot long boom, with the
satellite at its end, is raised out of the cargo bay to
provide clearance between the satellite and Shuttle during
deploy and retrieval operations.  The orientation of the
payload bay will result in the tethered satellite initially
deployed upward but at an angle of about 40 degrees behind
Atlantis' path.

     Using the tether reel's electric motors to unwind the
tether, an electric motor at the end of the boom to pull the
tether off of the reel and a thruster on the satellite that
pushes the satellite away from Atlantis, the satellite will
be moved away from the Shuttle. The deployment will begin
extremely slowly, with the satellite, after 1 hour has
elapsed since the tether was first unwound, moving away from
Atlantis at about one-half mile per hour. The initial
movement of the satellite away from the boom will be at less
than two-hundredths of 1 mile per hour.  The speed of deploy
will continue to increase, peaking after 1 and a half hours
from the initial movement to almost 4 miles per hour.

     At this point, when the satellite is slightly less than
1 mile from Atlantis, the rate of deployment will begin
slowing briefly, a maneuver that is planned to reduce the 40-
degree angle to 5 degrees and put the satellite in the same
plane almost directly overhead of Atlantis by the time that
about 3 miles of tether has been unwound.

     When the satellite is 3.7 miles from Atlantis, 2 and
one-half hours after the start of deployment, a one-quarter
of a revolution-per-minute spin will be imparted to it via
its attitude control system thrusters.  The slight spin is
needed for science operations with the satellite.

     After this, the speed of deployment will again be
increased gradually, climbing to a peak separation from
Atlantis of almost 5 mph about 4 hours into the deployment
when the satellite is about 9 miles distant.  From this
point, the speed with which the tether is fed out will
gradually decrease through the rest of the procedure, coming
to a stop almost 5 and half hours after the initial movement,
when the satellite is almost 12.5 miles from Atlantis.  Just
prior to the satellite arriving on station at 12.5 miles
distant, the quarter-revolution spin will be stopped briefly
to measure tether dynamics and then, a seven-tenths of a
revolution-per-minute spin will be imparted to it.  At full
deploy, the tension on the tether or the pull from the
satellite is predicted to be equivalent to about 10 pounds of
force.

     The tether, in total, is 13.7 miles long, allowing an
extra 1.2 miles of spare tether that is not planned to be
unwound during the mission.

Dynamics Functional Objectives

     During the deploy of TSS, several tests will be
conducted to explore control and dynamics of a tethered
satellite.  Models of deployment have shown that the longer
the tether becomes, the more stable the system becomes.  The
dynamics and control tests to be conducted during deploy also
will aid in preparing for retrieval of the satellite and
serve to verify the ability to control the satellite during
that operation.  During retrieval, it is expected that the
stability of the system will decrease as the tether is
shortened, just opposite the way stability increased as the
tether was lengthened during deploy.

     The dynamics tests involve maintaining a constant
tension on the tether and correcting any of several possible
disturbances to it.  Possible disturbances include:  a
bobbing motion, also called a plumb bob, where the satellite
bounces slightly on the tether causing it to alternately
slacken and tighten; a vibration of the tether, called a
libration, resulting in a clock-pendulum type movement of
tether and satellite; a pendulous motion of the satellite or
a rolling and pitching action by the satellite at the end of
the tether; and a lateral string mode disturbance, a motion
where the satellite and Shuttle are stable, but the tether is
moving back and forth in a "skip rope" motion.  All of these
disturbances may occur naturally and are not unexpected.

     The first test objectives will be performed before the
satellite reaches 200 yards from Atlantis and will involve
small firings of Atlantis' steering jets to test the
disturbances these may impart to the tether and satellite.
The crew will test three different methods of damping the
libration (clock pendulum) motion expected to be created in
the tether and the pendulous (rolling and pitching) motion
expected in the satellite.  First, using visual contact with
the satellite, to manually stabilize it from onboard the
Shuttle by remotely firing TSS's attitude thrusters.  Second,
using the telemetry information from the satellite to
manually fire the satellite's attitude thrusters.  Third,
using an automatic attitude control system for the satellite
via the Shuttle's flight control computers to automatically
fire the TSS thrusters and stabilize the system.

     Another test will be performed when the satellite is
about 2.5 miles from Atlantis.  Atlantis' autopilot will be
adjusted to allow the Shuttle to wobble by as much as 10
degrees in any direction before steering jets automatically
fire to maintain Atlantis' orientation.  The 10-degree
deadband will be used to judge any disturbances that may be
imparted to the satellite if a looser attitude control is
maintained by Atlantis.  The standard deadband, or degree of
wobble, set in Shuttle autopilot for the tethered satellite
operations is 2 degrees of wobble.  Tests using the wider
deadband will allow the crew and flight controllers to
measure the amount of motion the satellite and tether impart
to Atlantis.

     Dampening of the various motions expected to occur in
the tether and satellite will be accomplished while at 12.5
miles using electrical current flow through the tether.
During retrieval, test objectives will be met using a
combination of the Shuttle's steering jets, a built-in
dampening system at the end of the deploy boom and the
satellite's steering jets.

Tether Retrieval Operations

     Tether retrieval will occur more slowly than deployment.
The rate of tether retrieval, the closing rate between
Atlantis and the satellite, will build after 5 hours since
first movement to a peak rate of about 3 miles per hour.  At
that point, when the satellite is about 4 and a half miles
from Atlantis, the rate of retrieval will gradually decrease,
coming to a halt 10 hours after start of retrieval operations
when the satellite is 1.5 miles from Atlantis.

     The satellite will remain at 1.5 miles from Atlantis for
about 5 hours of science operations before the final
retrieval begins.  Final retrieval is expected to take about
2 hours.  A peak rate of closing between Atlantis and the
satellite of about 1.5 miles per hour will be attained just
after the final retrieval begins, and the closing rate will
decrease gradually through the remainder of the operation.
The closing rate at the time the satellite is docked to the
cradle at the end of the deployer boom is planned to be less
than one-tenth of 1 mile per hour.

     If the safety of the orbiter becomes a concern, the
tether will be cut and the satellite released or the
satellite and boom jettisoned.

TSS-1 SCIENCE OPERATIONS

     Speeding through the magnetized ionospheric plasma at
almost 5 miles per second, a 12-mile-long conducting tethered
system should create a variety of very interesting plasma-
electrodynamic phenomena.  These are expected to provide
unique experimental capabilities, including the ability to
collect an electrical charge and drive a large current system
within the ionosphere; generate high voltages (on the order
of 5 kilovolts) across the tether at full deployment; control
the satellite's electrical potential and its plasma sheath
(the layer of charged particles created around the
satellite); and generate low-frequency electrostatic and
electromagnetic waves.  It is believed that these
capabilities can be used to conduct controlled experimental
studies of phenomena and processes that occur naturally in
plasmas throughout the solar system, including Earth's
magnetosphere.

     A necessary first step toward these studies -- and the
primary science goal of the TSS-1 mission -- is to
characterize the electrodynamic behavior of the satellite-
tether-orbiter system.  Of particular interest is the
interaction of the system with the charged particles and
electric and magnetic fields in the ionosphere.

     A circuit must be closed to produce an electrical
current.  For example, in a simple circuit involving a
battery and a light bulb, current travels down one wire from
the battery to the bulb, through the bulb and back to the
battery via another wire completing the circuit.  Only when
the the circuit is complete will the bulb illuminate.  The
conductive outer skin of the satellite collects free
electrons from the space plasma, and the induced voltage
causes the electrons to flow down the conductive tether to
the Shuttle.  Then, they will be ejected back into space by
electron generator (Core equipment).

     Scientists expect the electrons to travel along magnetic
field lines in the ionosphere to complete the loop.  TSS-1
investigators will use a series of interdependent experiments
conducted with the electron guns and tether current-control
hardware, along with a set of diagnostic instruments, to
assess the nature of the external current loop within the
ionosphere and the processes by which current closure occurs
at the satellite and the orbiter.

Science Operations

     The TSS-1 mission is comprised of 11 scientific
investigations selected jointly by NASA and the Italian Space
Agency.  In addition, the U.S. Air Force's Phillips
Laboratory, by agreement, is providing an experimental
investigation.  Seven investigations provide equipment that
either stimulates or monitors the tether system and its
environment.  Two investigations will use ground-based
instruments to measure electromagnetic emissions from the
Tethered Satellite System as it passes overhead, and three
investigations were selected to provide theoretical support
in the areas of dynamics and electrodynamics.

     Most of the TSS-1 experiments require measurements of
essentially the same set of physical parameters, with
instrumentation from each investigation providing different
parts of the total set.  While some instruments measure
magnetic fields, others record particle energies and
densities, and still others map electric fields.  A complete
set of data on plasma and field conditions is required to
provide an accurate understanding of the space environment
and its interaction with the tether system.  TSS-1 science
investigations, therefore, are interdependent.  They must
share information and operations to achieve their objectives.
In fact, these investigations may be considered to be
different parts of a single complex experiment.

     The TSS-1 principal and associate investigators and
their support teams will be located in a special Science
Operations Center at the Mission Control Center in Houston.
During the tethered satellite portion of the STS-46 flight,
all 12 team leaders will be positioned at a conference table
in the operations center.  Science data will be available to
the entire group, giving them an integrated "picture" of
conditions observed by all the instruments.  Together, they
will assess performance of the experiment objectives.
Commands to change any instrument mode that affects the
overall data set must be approved by the group, because such
a change could impact the overall science return from the
mission.  Requests for adjustments will be relayed by the
mission scientist, the group's leader, to the science
operations director for implementation.

     The primary scientific data will be taken during the
approximately 10.5-hour phase (called "on-station 1") when
the satellite is extended to the maximum distance above the
Shuttle. Secondary science measurements will be taken prior
to and during deployment, during "on-station 1," and as the
satellite is reeled back to the orbiter.  However, after
accomplishment of the primary science objectives, tether
dynamic control takes priority over further science data
gathering.

     Science activities during the TSS-1 mission will be
directed by the science principal investigator team and
implemented by a payload cadre made up primarily of Marshall
Space Flight Center employees and their contractors.  Science
support teams for each of the 12 experiments will monitor the
science hardware status.  From the Science Operations Center
at Mission Control, the principal investigator team will be
able to evaluate the quality of data obtained, replan science
activities as needed and direct adjustments to the
instruments.  The cadre will be led by a science operations
director, who will work closely with the mission scientist,
the mission manager and Mission Control's payloads officer to
coordinate science activities.

     During the mission, most activities not carried out by
the crew will be controlled by command sequences, or timeline
files, written prior to the mission and stored in an onboard
computer.  For maximum flexibility, however, during all TSS
phases, modifications to these timeline files may be
uplinked, or commands may be sent in real-time from the
Science Operations Center to the on-board instruments.


SCIENCE INVESTIGATIONS

TSS Deployer Core Equipment and Satellite Core Equipment
(DCORE/SCORE)

Principal Investigator:

Dr. Carlo Bonifazi
Italian Space Agency, Rome, Italy

     The Tethered Satellite System Core Equipment controls
the electrical current flowing between the satellite and the
orbiter.  It also makes a number of basic electrical and
physical measurements of the system.

     Mounted on the aft support structure in the Shuttle
cargo bay, the Deployer Core Equipment features two identical
electron generators (the prime and the back up) that can each
eject up to 750 milli-amperes (3/4 amp) of current from the
system.  A master switch, the electron generator control
switches, power distribution and electronic control unit, and
command and data interfaces also are included in the deployer
core package.  A voltmeter measures tether potential with
respect to the orbiter structure, and a vacuum gauge measures
ambient gas pressure to prevent operations if pressure
conditions might cause electrical arcing.

     Core equipment located on the satellite itself includes
an ammeter to measure tether current collected on the skin of
the TSS-1 satellite and an accelerometer-gyro three exes
packages to measure satellite motion and attitude.

Research on Orbital Plasma Electrodynamics (ROPE)

Principal Investigator:

Dr. Nobie Stone
NASA Marshall Space Flight Center, Huntsville, Ala.

     This experiment studies behavior of ambient charged
particles in the ionosphere and ionized neutral particles
around the satellite under a variety of conditions.
Comparisons of readings from its instruments should allow
scientists to determine where the particles come from that
make up the tether current as well as the distribution and
flow of charged particles in the space immediately
surrounding the satellite.

     The Differential Ion Flux Probe, mounted on the end of
the satellite's fixed boom, measures the energy, temperature,
density and direction of ambient ions that flow around the
satellite as well as neutral particles that have been ionized
in its plasma sheath and accelerated outward by the sheath's
electric field.

     The Soft Particle Energy Spectrometer is actually five
electrostatic analyzers -- three mounted at different
locations on the surface of the satellite itself, and the
other two mounted with the Differential Ion Flux Probe on the
boom.  Taken together, measurements from the two boom-mounted
sensors can be used to determine the electrical potential of
the sheath of ionized plasma surrounding the satellite.  The
three satellite-mounted sensors will measure geometric
distribution of the current to the satellite's surface.

Research on Electrodynamic Tether Effects (RETE)

Principal Investigator:

Dr. Marino Dobrowolny
Italian National Research Council, Rome, Italy

     This experiment measures the electrical potential in the
plasma sheath around the satellite and identifies waves
excited by the satellite and tether system.  The instruments
are located in two canisters at the end of the satellite's
extendible booms.  As the satellite spins, the booms are
extended, and the sensors sweep the plasma around the entire
circumference of the spacecraft.  To produce a profile of the
plasma sheath, measurements of direct-current potential and
electron currents are made both while the boom is fully
extended and as it is being extended or retracted.  The same
measurements, taken at a fixed distance from the spinning
satellite, produce a map of the angular structure of the
sheath.

Magnetic Field Experiment for TSS Missions (TEMAG)

Principal Investigator:

Prof. Franco Mariani
Second University of Rome, Italy

     The primary goal of this investigation is to map the
levels and fluctuations in magnetic fields around the
satellite.  Two magnetometers -- very accurate devices for
measuring such fields -- are located on the fixed boom of the
satellite, one at its end and the other at its midpoint.
Comparing measurements from the two magnetometers allows
real-time estimates to be made of unwanted disturbances to
the magnetic fields produced by the presence of satellite
batteries, power systems, gyros, motors, relays and other
magnetic material.  After the mission, the variable effects
of switching satellite subsystems on and off, of thruster
firings and of other operations that introduce magnetic
disturbances will be modeled on the ground, so these
satellite effects can be subtracted from measurements of the
ambient magnetic fields in space.

Shuttle Electrodynamic Tether System (SETS)

Principal Investigator:

Dr. Peter Banks
University of Michigan, Ann Arbor

     This investigation studies the ability of the tethered
satellite to collect electrons by determining current and
voltage of the tethered system and measuring the resistance
to current flow in the tether itself.  It also explores how
tether current can be controlled by the emission of electrons
at the orbiter end of the system and characterizes the charge
the orbiter acquires as the tether system produces power,
broadcasts low-frequency radio waves and creates
instabilities in the surrounding plasma.

     The hardware is located on the support structure in the
orbiter cargo bay.  In addition to three instruments to
characterize the orbiter's charge, the experiment includes a
fast-pulse electron accelerator used to help neutralize the
orbiter's charge.  It is located close to the core electron
gun and aligned so beams from both are parallel.  The fast-
pulse accelerator acts as a current modulator, emitting
electron beams in recognizable patterns to stimulate wave
activity over a wide range of frequencies.  The beams can be
pulsed with on/off times on the order of 100 nanoseconds.

Shuttle Potential and Return Electron Experiment (SPREE)

Associate Investigators:

Dr. Dave Hardy and Capt. Marilyn Oberhardt
Dept. of the Air Force, Phillips Laboratory, Bedford, Mass.

     Also located on the support structure, this experiment
will measure populations of charged particles around the
orbiter.  Measurements will be made prior to deployment to
assess ambient space conditions as well as during active TSS-
1 operations.  The measurements will determine the level of
orbiter charging with respect to the ambient space plasma,
characterize the particles returning to the orbiter as a
result of TSS-1 electron beam ejections and investigate local
wave-particle interactions produced by TSS-1 operations.
Such information is important in determining how the Tethered
Satellite System current is generated, and how it is affected
by return currents to the orbiter.  The experiment uses two
sets of two nested electrostatic analyzers each, which rotate
at approximately 1 revolution per minute, sampling the
electrons and ions in and around the Shuttle's cargo bay.


Tether Optical Phenomena Experiment (TOP)

Associate Investigator:

Dr. Stephen Mende
Lockheed, Palo Alto Research Laboratory, Palo Alto, Calif.

     This experiment uses a hand-held, low-light-level TV
camera system operated by the crew, to provide visual data to
allow scientists to answer a variety of questions about
tether dynamics and optical effects generated by TSS-1.  The
imaging system will operate in four configurations:
filtered, interferometer, spectrographic and filtered with a
telephoto lens.  In particular, the experiment will image the
high voltage plasma sheath surrounding the satellite when it
is reeled back toward the orbiter near the end of the
retrieval stage of the mission.

Investigation of Electromagnetic Emissions for Electrodynamic
Tether (EMET)

Principal Investigator:

Dr. Robert Estes
Smithsonian Astrophysical Observatory, Cambridge, Mass.

Observations at the Earth's Surface of Electromagnetic
Emission by TSS (OESEE)

Principal Investigator:

Dr. Giorgio Tacconi, University of Genoa, Italy

     The main goal of these experiments is to determine how
well the Tethered Satellite System can broadcast from space.
Ground-based radio transmissions, especially below 15 ekilohertz, are inefficient since most of the power supplied
to the antenna -- large portions of which are buried -- is
absorbed by the ground.  Since the Tethered Satellite System
operates in the ionosphere, it should radiate waves more
efficiently.  Magnetometers at several locations in a chain
of worldwide geomagnetic observatories and extremely low-
fequency receivers at the Arecibo Radio Telescope facility,
Puerto Rico, and other sites around the world, will try to
measure the emissions produced and track direction of the
waves when electron accelerators pulse tether current over
specific land reference points.  An Italian ocean surface and
ocean bottom observational facility also provides remote
measurements for TSS-1 emissions.



The Investigation and Measurement of Dynamic Noise in the TSS
(IMDN)

Principal Investigator:

Dr. Gordon Gullahorn
Smithsonian Astrophysical Observatory, Cambridge, Mass.

Theoretical and Experimental Investigation of TSS Dynamics
(TEID)

Principal Investigator:

Prof. Silvio Bergamaschi
Institute of Applied Mechanics, Padua University, Padua,
Italy

     These two investigations will analyze data from a
variety of instruments to examine Tethered Satellite System
dynamics or oscillations over a wide range of frequencies.
Primary instruments will be accelerometers and gyros on board
the satellite, but tether tension and length measurements and
magnetic field measurements also will be used.  The dynamics
will be observed in real-time at the Science Operations
Center and later, subjected to detailed post-flight analysis.
Basic theoretical models and simulations of tether movement
will be verified, extended or corrected as required.  Then
they can be used confidently in the design of future systems.

Theory and Modeling in Support of Tethered Satellite
Applications (TMST)

Principal Investigator:

Dr. Adam Drobot
Science Applications International Corp., McLean, Va.

     This investigation provides theoretical electro-dynamic
support for the mission.  Numerical models were developed of
anticipated current and voltage characteristics, plasma
sheaths around the satellite and the orbiter and of the
system's response to the operation of the electron
accelerators.  These models tell investigators monitoring the
experiments from the ground what patterns they should expect
to see in the data.


THE TSS-1 TEAM

     Within NASA, the Tethered Satellite System program is
directed by the Office of Space Flight and the Office of
Space Science and Applications.  The Space Systems Projects
Office at the Marshall Space Flight Center, Huntsville, Ala.,
has responsibility for project management and overall systems
engineering.  Experiment hardware systems were designed and
developed by the U.S. and Italy.  Responsibility for
integration of all hardware, including experiment systems on
the MPESS pallet, is assigned to the project manager at the
Marshall center.  The Kennedy Space Center, Florida, is
responsible for launch-processing and launch of the TSS-1
payload.  The Johnson Space Center, Houston, has
responsibility for TSS-1/STS integration and mission
operations.

     R.J. Howard of the Office of Space Science and
Applications, NASA Headquarters, Washington, D.C., is the
TSS-1 Science Payload Program Manager.  The TSS Program
Manager is Tom Stuart of the Office of Space Flight, NASA
Headquarters.  Billy Nunley is NASA Project Manager and TSS-1
Mission Manager at the Marshall Space Flight Center.  Dr.
Nobie Stone, also of Marshall, is the NASA TSS-1 Mission
Scientist, the TSS Project Scientist and Co-chairman of the
Investigator Working Group.

     For the Italian Space Agency responsible for the
satellite, Core equipment and Italian experiments development
and for the science integration into the satellite, Dr.
Gianfranco Manarini is Program Manager for TSS-1, while the
Program Scientist is Dr. F. Mariani.  Dr. Marino Dobrowolny
is the Project Scientist for the Italian Space Agency, and
Co-chairman of the investigator group.  Dr. Maurizio Candidi
is the Mission Scientist for the Italian Space Agency.

     Martin Marietta, Denver, Colo., developed the tether and
control system deployer for NASA.  Alenia Spazio in Turin,
Italy, developed the satellite and the Core equipment for the
Italian Space Agency.


TSS-1 SCIENCE INVESTIGATIONS

            Title                    Institution (Nation)

Research on Electrodynamic           CNR or Italian National
Tether Effects                       Research Council (Italy)

Research on Orbital Plasma           NASA/MSFC (U.S.)
Electrodynamics

Shuttle Electrodynamic Tether Sys.  University of Michigan
(U.S.)

Magnetic Field Experiments          Second University of Rome
for TSS Missions                    (Italy)

Theoretical & Experimental          Univ. of Padua (Italy)
Investigation of TSS Dynamics

Theory & Modeling in Support         SAIC (U.S.)
of Tethered Satellite

Investigation of Electromagnetic     Smithsonian
Astrophysical
Emissions for Electrodynamic         Observatory (U.S.)
Tether

Investigation and Measurement of     Smithsonian
Astrophysical
Dynamic Noise in TSS                 Observatory (U.S.)

Observation on Earth's Surface of    Univ. of Genoa (Italy)
Electromagnetic Emissions by TSS

Deployer Core Equipment and Satellite   ASI (Italy)
Core Equipment

Tether Optical Phenomena Experiment  Lockheed (U.S.)

Shuttle Potential & Return           Dept. of the Air Force
Electron Experiment                  Phillips Laboratory
(U.S.)


EUROPEAN RETRIEVABLE CARRIER (EURECA)

     The European Space Agency's (ESA) EURECA will be
launched by the Space Shuttle and deployed at an altitude of
425 km.  It will ascend, using its own propulsion, to its
operational orbit of 515 km.  After 6 to 9 months in orbit,
it will descend to the lower orbit where it will be retrieved
by another orbiter and brought back to Earth.  It will
refurbished and equipped for the next mission.

     The first mission (EURECA-1) primarily will be devoted
to research in the fields of material and life sciences and
radiobiology, all of which require a controlled microgravity
environment.  The selected microgravity experiments will be
carried out in seven facilities.  The remaining payload
comprises space science and technology.

     During the first mission, EURECA's residual carrier
accelerations will not exceed 10-5g.  The platform's altitude
and orbit control system makes use of magnetic torquers
augmented by cold gas thrusters to keep disturbance levels
below 0.3 Nm during the operational phase.

Physical characteristics

o  Launch mass                                        4491 kg
o  Electrical power solar array                         5000w
o  Continuous power to EURECA experiments...............1000w
o  Launch configuration           dia:  4.5m,  length:  2.54m
o  Volume                                               40.3m
o  Solar array extended                             20m x 3.5

User friendly

     Considerable efforts have been made during the design
and development phases to ensure that EURECA is a "user
friendly" system.  As is the case for Spacelab, EURECA has
standardized structural attachments, power and data
interfaces.  Unlike Spacelab, however, EURECA has a
decentralized payload control concept.  Most of the onboard
facilities have their own data handling device so that
investigators can control the internal operations of their
equipment directly.  This approach provides more flexibility
as well as economical advantages.

Operations

     EURECA is directly attached to the Shuttle cargo bay by
means of a three-point latching system.  The spacecraft has
been designed with a minimum length and a close-to-optimum
length-to-mass ratio, thus helping to keep down launch and
retrieval costs.

     All EURECA operations will be controlled by ESA's Space
Operations Centre (ESOC) in Darmstadt, Germany.  During the
deployment and retrieval operations, ESOC will function as a
Remote Payload Operations Control


EURECA-1L

Centre to NASA's Mission Control Center, Houston, and the
orbiter will be used as a relay station for all the commands.
In case of unexpected communication gaps during this period,
the orbiter crew has a back-up command capability for
essential functions.

     Throughout the operational phase, ESOC will control
EURECA through two ground stations at Maspalomas, ---, and
Kourou, French Guiana.  EURECA will be in contact with its
ground stations for a relatively short period each day.  When
it is out of contact, or "invisible", its systems operate
with a high degree of autonomy, performing failure detection,
isolation and recovery activities to safeguard ongoing
experimental processes.

     An experimental advanced data relay system, the Inter-
orbit Communication package, is included in the first
payload.  This package will communicate with the European
Olympus Communication Satellite to demonstrate the possible
improvements for future communications with data relay
satellites.  As such a system will significantly enhance
realtime data coverage, it is planned for use on subsequent
EURECA missions to provide an operational service via future
European data relay satellites.


EURECA Retrievable Carrier

Structure

     The EURECA structure is made of high strength carbon-
fibre struts and titanium nadal points joined together to
form a framework of cubic elements.  This provides relatively
low thermal distortions, allows high alignment accuracy and
simple analytical verification, and is easy to assemble and
maintain.  Larger assemblies are attached to the nadal
points.  Instruments weighing less than 100 kg are assembled
on standard equipment support panels similar to those on a
Spacelab pallet.

Thermal Control

     Thermal control for EURECA combines active and passive
heat transfer and radiation systems.  Active transfer,
required for payload facilities which generated more heat, is
achieve by means of a freon cooling loop which dissipates the
thermal load through two radiators into space.  The passive
system makes use of multilayer insulation blankets combined
with electrical heaters.  During nominal operations, the
thermal control subsystem rejects a maximum heat load of
about 2300 w.

Electrical Power

     The electrical power subsystem generates, stores,
conditions and distributes power to all the spacecraft
subsystems and to the payload.  The deployable and retracable
solar arrays, with a combined raw power output of some 5000 w
together with four 40 amp-hour (Ah) nickel-cadmium batteries,
provide the payload with a continuous power of 1000 w,
nominally at 28 volts, with peak power capabilities of up to
1500 w for several minutes.  While EURECA is in the cargo
bay, electric power is provided by the Shuttle to ensure that
mission critical equipment is maintained within its
temperature limits.

 Attitude and Orbit Control

     A modular attitude and orbit control subsystem (AOCS) is
used for attitude determination and spacecraft orientation
and stabilization during all flight operations and orbit
control manoeuvres.  The AOCS has been designed for maximum
autonomy.  It will ensure that all mission requirements are
met even in case of severe on-board failures, including non-
availability of the on-board data handling subsystem for up
to 48 hours.

     An orbit transfer assembly, consisting of two redundant
sets of four thrusters, is used to boost EURECA to its
operation attitude at 515 km and to return it to its
retrieval orbit at about 300 km.  The amount of onboard
propellant hydrazine is sufficient for the spacecraft to fly
different mission profiles depending on its nominal mission
duration which may be anywhere between 6 and 9 months.

     EURECA is three-axis stabilized by means of a magnetic
torque assembly together with a nitrogen reaction control
assembly (RCA).  This specific combination of actuators was
selected because its' control accelerations are well below
the microgravity constraints of the spacecraft.  The RCA cold
gas system can be used during deployment and retrieval
operations without creating any hazards for the Shuttle.


Communications and Data Handling

     EURECA remote control and autonomous operations are
carried out by means of the data handling subsystem (DHS)
supported by the telemetry and telecommand subsystems which
provide the link to and from the ground segment.  Through the
DHS, instructions are stored and executed, telemetry data is
stored and transmitted, and the spacecraft and its payload
are controlled when EURECA is no longer "visible" from the
ground station.


EURECA SCIENCE

Solution Growth Facility (SGF)

Principal Investigator:

J.C. Legros
Universit Libre de Bruxelles, Brussels, Belgium

     The Solution Growth Facility (SGF) is a multi-user
facility dedicated to the growth of monocrystals from
solution, consisting of a set of four reactors and their
associated control system.

     Three of the reactors will be used for the solution
growth of crystals.  These reactors have a central buffer
chamber containing solvent and two reservoirs containing
reactant solutions.  The reservoirs are connected to the
buffer chamber by valves which allow the solutions to diffuse
into the solvent and hence, to crystallize.

     The fourth reactor is divided into twenty individual
sample tubes which contain different samples of binary
organic mixtures and aqueous electrolyte solutions.  This
reactor is devoted to the measurement of the Soret
coefficient, that is, the ratio of thermal to isothermal
diffusion coefficient.

     The SGF has been developed under ESA contract by Laben
and their subcontractors Contraves and Terma.

Protein Crystallization Facility (PCF)

Principal Investigator:

W. Littke
Chemisches Laboratorium, Universitt Freiburg, Freiburg,
Germany

     The Protein Crystallization Facility (PCF) is a multi-
user solution growth facility for protein crystallization in
space.  The object of the experiments is the growth of
single, defect-free protein crystals of high purity and of a
size sufficient to determine their molecular structure by x-
ray diffraction.  This typically requires crystal sizes in
the order of a few tenths of a millimeter.

     The PCF contains twelve reactor vessels, one for each
experiment.  Each reactor, which is provided with an
individually controlled temperature environment, has four
chambers -- one containing the protein, one containing a
buffer solution and two filled with salt solutions.  When the
reactors have reached their operating temperatures, one of
the salt solution chambers, the protein chamber and the
buffer solution chamber are opened.  Salt molecules diffuse
into the buffer chamber causing the protein solution to
crystalize.  At the end of the mission the second salt
solution chamber is activated to increase the salt
concentration.  This stabilizes the crystals and prevents
them from dissolving when individual temperature control for
the experiments ceases and the reactors are maintained at a
common storage temperature.

     One particular feature of the PCF is that the
crystallization process can be observed from the ground by
means of a video system.

     The PCF has been developed under ESA contract by MBB
Deutsche Aerospace and their subcontractors Officine Galileo
and Reusser.

Exobiology And Radiation Assembly (ERA)

Principal Investigator:

H. Bucker
Institut fur Flugmedizin Abteilung Biophysik, German
Aerospace Research Establishment (DLR), Cologne, Germany

     The Exobiology and Radiation Assembly (ERA) is a multi-
user life science facility for experiments on the biological
effects of space radiation.  Our knowledge of the interaction
of cosmic ray particles with biological matter, the synergism
of space vacuum and solar UV, and the spectral effectiveness
of solar UV on viability should be improved as a result of
experiments carried out in the ERA.

     The ERA consists of deployable and fixed experiment
trays and a number of cylindrical stacks, known as Biostacks,
containing biological objects such as spores, seeds or eggs
alternated with radiation and track detectors.  An electronic
service module also is included in the facility.  The
deployable trays carry biological specimens which are exposed
to the different components of the space radiation
environment for predetermined periods of time.  The duration
of exposure is controlled by means of shutters and the type
of radiation is selected by the use of optical bandpass
filters.

The ERA has been developed under ESA contract by Sira Ltd..


Multi-Furnace Assembly (MFA)

Principal Investigator:

A. Passerone
Ist. di Chimica Fisica Applicata dei Materiali, National
Research Council (CNR), Genova, Italy

     The Multi-Furnace Assembly (MFA) is a multi-user
facility dedicated to material science experiments.  It is a
modular facility with a set of common system interfaces which
incorporates twelve furnaces of three different types, giving
temperatures of up to 1400xC.  Some of the furnaces are
provided by the investigators on the basis of design
recommendations made by ESA.  The remainder are derived from
furnaces flown on other missions, including some from
sounding rocket flights.  These are being used on EURECA
after the necessary modifications and additional
qualification.  The experiments are performed sequentially
with only one furnace operating at any one time.

     The MFA has been developed under ESA contract by
Deutsche Aerospace, ERNO Raumfahrttechnik and their
subcontractors SAAB, Aeritalia, INTA and Bell Telephone.

Automatic Mirror Furnace (AMF)

Principal Investigator:

K.W. Benz
Kristallographisches Institut, Universitt Freiburg,
Freiburg, Germany

     The Automatic Mirror Furnace (AMF) is an optical
radiation furnace designed for the growth of single, uniform
crystals from the liquid or vapor phases, using the traveling
heater or Bridgman methods.

     The principal component of the furnace is an ellipsoidal
mirror.  The experimental material is placed at the lower
ring focus of the mirror and heated by radiation from a 300 w
halogen lamp positioned at the upper focus.  Temperatures of
up to 1200xC can be achieved, depending on the requirements
of individual samples.  Seven lamps are available and up to
23 samples can be processed in the furnace.

     As the crystal grows, the sample holder is withdrawn
from the mirror assembly at crystallization speed, typically
2 mm/day, to keep the growth site aligned with the furnace
focus.  The sample also is rotated while in the furnace.

     The AMF is the first of a new generation of crystal
growth facilities equipped with sample and lamp exchange
mechanisms.  Fully automatic operations can be conducted in
space during long microgravity missions on free flying
carriers.  During a 6 month mission, about 20 different
crystal growth experiments can be performed.

     The AMF has been developed under ESA contract by Dornier
Deutsche Aerospace and their subcontractors Laben, ORS and
SEP.

Surface Forces Adhesion Instrument (SFA)

Principal Investigator:

G. Poletti
Universita di Milano, Milan, Italy

     The Surface Forces Adhesion instrument (SFA) has been
designed to study the dependence of surface forces and
interface energies on physical and chemical-physical
parameters such as surface topography, surface cleanliness,
temperature and the deformation properties of the contacting
bodies.  The SFA experiment aims at refining current
understanding of adhesion-related phenomena, such as friction
and wear, cold welding techniques in a microgravity
environment and solid body positioning by means of adhesion.

     Very high vacuum dynamic measurements must be performed
in microgravity conditions because of the extreme difficulty
experienced on Earth in controlling the physical parameters
involved.  As a typical example, the interface energy of a
metallic sphere of 1 g mass contacting a pane target would be
of the order of 10-3 erg. corresponding to a potential
gravitational energy related to a displacement of 10-5 mm.
In the same experiment performed on the EURECA platform, in a
10 to 100,000 times lower gravity environment, this energy
corresponds to a displacement of 1 mm, thus considerably
improving measurements and reducing error margins.

     The SFA instrument has been funded by the Scientific
Committee of the Italian Space Agency (ASI) and developed by
the University of Milan and their subcontractors
Centrotechnica, Control Systems and Rial.

High Precision Thermostat Instrument (HPT)

Principal Investigator:

G. Findenegg
Ruhr Universitt Bochum, Bochum, Germany

     Basic physics phenomena around the critical point of
fluids are not, as yet, fully understood.  Measurements in a
microgravity environment, made during the German mission D-1,
seem to be at variance with the expected results.  Further
investigations of critical phenomena under microgravity
conditions are of very high scientific value.

     The High Precision Thermostat (HPT) is an instrument
designed for long term experiments requiring microgravity
conditions and high precision temperature measurement and
control.  Typical experiments are "caloric", "critical point"
or "phase transition" experiments, such as the "Adsorption"
experiment designed for the EURECA mission.

     This experiment will study the adsorption of Sulphur
Hexafluoride (SF6), close to its critical point (Tc=45.55xC,
pc=0.737 g/cm3) on graphitised carbon.  A new volumetric
technique will be used for the measurements of the adsorption
coefficient at various temperatures along the critical
isochore starting from the reference temperature in the one-
phase region (60x) and approaching the critical temperature.
The results will be compared with 1g measurements and
theoretical predictions.

     The HPT has been developed under DLR contract by
Deutsche Aerospace, ERNO Raumfahrttechnik and their
subcontractor Kayser-Threde GmbH.


Solar Constant And Variability Instrument (SOVA)

Principal Investigator:

D. Crommelynck
Institut Royal Mtorologique de Belgique (IRMB), Brussels,
Belgium

     The Solar Constant and Variability Instrument (SOVA) is
designed to investigate the solar constant, its variability
and its spectral distribution, and measure:

  o  fluctuations of the total and spectral solar irradiance
within periods of a few minutes up to several hours and with
a resolution of 10-6 to determine the pressure and gravity
modes of the solar oscillations which carry information on
the internal structure of the sun;

  o  short term variations of the total and spectral solar
irradiance within time scales ranging from hours to few
months and with a resolution of 10-5 for the study of energy
redistribution in the solar convection zone.  These
variations appear to be associated with solar activities (sun
spots);

  o  long term variations of the solar luminosity in the time
scale of years (solar cycles) by measuring the absolute solar
irradiance with an accuracy of better than 0.1 percent and by
comparing it with previous and future measurements on board
Spacelab and other space vehicles.  This is of importance for
the understanding of solar cycles and is a basic reference
for climatic research.

     The SOVA instrument has been developed by the IRMB, by
the Physikalisch-Meteorologishces Observatorium World
Radiation Center (PMOD/WRC) Davos, Switzerland, and by the
Space Science Department (SSD) of the European Space Agency
(ESA-ESTEC), Noordwijk, The Netherlands.

Solar Spectrum Instrument (SOSP)

Principal Investigator:

G. Thuillier
Service d'Aeronomie du Centre National de Recherche
Scientifique (CNRS), Verrieres le Buisson, France

     The Solar Spectrum Instrument (SOSP) has been designed
for the study of solar physics and the solar-terrestrial
relationship in aeronomy and climatology.  It measures the
absolute solar irradiance and its variations in the spectral
range from 170 to 3200 nm, with an expected accuracy of 1
percent in the visible and infrared ranges and 5 percent in
the ultraviolet range.

     Changes in the solar irradiance mainly relate to the
short-term solar variations that have been observed since
1981 by the Solar Maximum spacecraft, the variations related
to the 27-day solar rotation period and the long-term
variations related to the 11-year sun cycles.  While the
short term variations can be measured during one single
EURECA flight mission, two or three missions are needed to
assess the long term variations.

     SOSP has been developed by the Service d'Aeronomie of
the CNRS, the Institut d'Aeronomie Spatiale de Belgique
(IASB), the Landessternwarte Koenigstuhl and the Hamburger
Sternwarte.

Occultation Radiometer Instrument (ORA)

Principal Investigator:

E. Arijs
Belgisch Instituut voor Ruimte Aeronomie (BIRA), Brussels,
Belgium

     The Occultation Radiometer instrument (ORA) is designed
to measure aerosols and trace gas densities in the Earth's
mesosphere and stratosphere.  The attenuation of the various
spectral components of the solar radiation as it passes
through the Earth's atmosphere enables vertical abundance
profiles for ozone, nitrogen dioxide, water vapor, carbon
dioxide and background and volcanic aerosols to be determined
for altitudes between 20 and 100 km.

     The ORA instrument has been developed by the Institut
d'Aeronomie Spatiale, and the Clarendon Laboratory of the
University of Oxford.

Wide Angle Telescope (WATCH)

Principal Investigator:

N. Lund
Danish Space Research Institute, Lyngby, Denmark

     The Wide Angle Telescope (WATCH) is designed to detect
celestial gamma and x-ray sources with photon energies in the
range 5 to 200 keV and determine the position of the source.

     The major objective of WATCH is the detection and
localization of gamma-ray bursts and hard x-ray transients.
Persistent x-ray sources also can be observed.

     Cosmic gamma-ray bursts are one of the most extreme
examples of the variability of the appearance of the x-ray
sky.  They rise and decay within seconds, but during their
life they outshine the combined flux from all other sources
of celestial x- and gamma rays by factors of up to a
thousand.

     Less conspicuous, but more predictable are the x-ray
novae which flare regularly, typically with intervals of a
few years.  In the extragalactic sky, the "active galactic
nuclei" show apparently are random fluctuations in their x-
ray luminosity over periods of days or weeks.

     WATCH will detect and locate these events.  The data
from the experiment can be used to provide light curves and
energy for the sources.  The data also may be searched for
regularities in the time variations related to orbital
movement or rotation or for spectral features that yield
information about the source.  Additionally, other, more
powerful sky observation instruments can be alerted to the
presence of objects that WATCH has detected as being in an
unusual state of activity.

WATCH has been developed by the Danish Space Research
Institute.

Timeband Capture Cell Experiment (TICCE)

Principal Investigator:

J.A.M. McDonnell
Unit for Space Science, Physics Laboratory
University of Kent, United Kingdom

     The Timeband Capture Cell Experiment (TICCE) is an
instrument designed for the study of the microparticle
population in near-Earth space -- typically Earth debris,
meteoroids and cometary dust.  The TICCE will capture micron
dimensioned particles with velocities in excess of 3 km/s and
store the debris for retrieval and post-mission analysis.

     Particles detected by the instrument pass through a
front foil and into a debris collection substrate positioned
100 nm behind the foil.  Each perforation in the foil will
have a corresponding debris site on the substrate.  The foil
will be moved in 50 discrete steps during the six month
mission, and the phase shift between the debris site and the
perforation will enable the arrival timeband of the particle
to be determined.  Between 200 and 300 particles are expected
to impact the instrument during the mission.  Ambiguities in
the correlation of foil perforations and debris sites will
probably occur for only a few of the impacts.

     Elemental analysis of the impact sites will be
performed, using dispersive x-ray techniques, once the
instrument has returned to Earth.

     TICCE has been developed by the University of Kent.  Its
structural support has been sponsored by ESA and
subcontracted to SABCA under a Deutsche Aerospace ERNO
Raumfahrttechnik contract.
Radio Frequency Ionization Thruster Assembly (RITA)

Principal Investigator:

H. Bassner
MBB Deutsche Aerospace, Munich, Germany

     The Radio Frequency Ionization Thruster Assembly (RITA)
is designed to evaluate the use of electric propulsion in
space and to gain operational experience before endorsing its
use for advanced spacecraft technologies.

     The space missions now being planned - which are both
more complex and of longer duration - call for increased
amounts of propellant for their propulsion systems which, in
turn, leads to an increase in the overall spacecraft mass to
the detriment of the scientific or applications payload.
Considerable savings can be made in this respect by the use
of ion propulsion systems, wherein a gas is ionized and the
positive ions are them accelerated by an electric field.  In
order to avoid spacecraft charging, the resulting ion beam is
then neutralized by an electron emitting device, the
neutralizer.  The exhaust velocities obtained in this way are
about an order of magnitude higher than those of chemical
propulsion systems.

     RITA has been developed under ESA and German Ministry
for Research and Technology (BMFT) contract by Deutsche
Aerospace ERNO Raumfahrttechnik.

Inter-Orbit Communication (IOC)

R. Tribes
French Space Agency (CNES) Project Manager, CNES-IOC
Toulouse, France

N. Neale
ESA Project Manager, ESTEC-CD
Noordwijk, The Netherlands

     The Inter-Orbit Communication (IOC) instrument is a
technological experiment designed to provide a pre-
operational inflight test and demonstration of the main
functions, services and equipment typical of those required
for a data relay system, namely:

o  bi-directional, end-to-end data transmission between the
user spacecraft and a dedicated ground station via a relay
satellite in the 20/30 GHz frequency band;

o  tracking of a data relay satellite;

o  tracking of a user spacecraft;

o  ranging services for orbit determination of a user
spacecraft via a relay satellite.

     In this case, the EURECA platform is the user spacecraft
and the ESA communications satellite Olympus the relay
satellite.  One of the Olympus steerable spot beam antennas
will be pointed towards the IOC on EURECA and the other
towards the IOC ground station.  The IOC instrument is
provided with a mobile directional antenna to track Olympus.

     The IOC has been developed under ESA contract by CNES
and their subcontractors Alocatel Espace, Marconi Space
Systems, Laben, Matra Espace, Sener, Alcatel Bel, AEG-
Telefunken, ETCA, TEX, MDS and COMDEV.

Advanced Solar Gallium Arsenide Array (ASGA)

Principal Investigator:

C. Flores
CISE SPA, Segrate, Italy

     The Advanced Solar Gallium Arsenide Array (ASGA) will
provide valuable information on the performance of gallium
arsenide (GaAs) solar arrays and on the effects of the low
Earth orbit environment on their components.  These solar
cells, already being used in a trial form to power the Soviet
MIR space station, are expected to form the backbone of the
next generation of compact, high power-to-weight ratio
European solar energy generators.

     The most significant environmental hazards encountered
arise from isotropic proton bombardment in the South Atlantic
Anomaly, high frequency thermal cycling fatigue of solar cell
interconnections and the recently discovered atomic oxygen
erosion of solar array materials.  Although a certain amount
of knowledge may be gained from laboratory experiments, the
crucial confirmation of the fidelity of the GaAs solar array
designs awaits the results of flight experiments.

     The project has been sponsored by the Italian Space
Agency (ASI) and developed by CISE with its subcontractor,
Carlo Gavazzi Space.  The planar solar module has been
assembled by FIAR.  The miniature Cassegranian concentrator
components have been developed in collaboration with the
Royal Aircraft Establishments and Pilkington Space
Technology.

     EURECA has been developed under ESA contract by Deutsche
Aerospace, ERNO Raumfahrttechnik, (Germany), and their
subcontractors Sener, (England), AIT, (Italy), SABCA,
(Belgium), AEG, (Germany), Fokker, (The Netherlands), Matra,
(France), Deutsche Aerospace, ERNO Raumfahrttechnik,
(Germany), SNIA-BPD, (Italy), BTM, (Belgium), and Laben,
(Italy).

F. Schwan - Industrial Project Manager
Deutsche Aerospace, ERNO Raumfahrttechnik, Bremen, Germany
W. Nellessen - ESA Project Manager
ESTEC MR, Noordwijk, The Netherlands


EVALUATION OF OXYGEN INTERACTION WITH MATERIALS/TWO PHASE
MOUNTING PLATE EXPERIMENT (EOIM-III/TEMP 2A-3)

EOIM

     The Evaluation of Atomic Oxygen Interactions with
Materials (EOIM) payload will obtain accurate reaction rate
measurements of the interaction of space station materials
with atomic oxygen.  It also will measure the local Space
Shuttle environment, ambient atmosphere and interactions
between the two.  This will improve the understanding of the
effect of the Shuttle environment on Shuttle and payload
operations and will update current models of atmospheric
composition.  EOIM also will assess the effects of
environmental and material parameters on reaction rates.

     To make these measurements, EOIM will use an ion-neutral
mass spectrometer to obtain aeronomy measurements and to
study atom-surface interaction products.  The package also
provides a mass spectrometer rotating carousel system
containing RmodeledS polymers for mechanistic studies.  EOIM
also will study the effects of mechanical stress on erosion
rates of advanced composites and the effects of temperature
on reaction rates of disk specimens and thin films.  Energy
accommodations on surfaces and surface-atom emission
characteristics concerning surface recession will be measured
using passive scatterometers.  The payload also will assess
solar ultraviolet radiation reaction rates.

     The environment monitor package will be activated pre-
launch, while the remainder of the payload will be activated
after payload bay door opening.  Experiment measurements will
be made throughout the flight, and the package will be
powered down during de-orbit preparations.

TEMP

     The Two Phase Mounting Plate Experiment (TEMP 2A-3) has
two-phase mounting plates, an ammonia reservoir, mechanical
pumps, a flowmeter, radiator and valves, and avionics
subsystems.  The TEMP is a two-phase thermal control system
that utilizes vaporization to transport large amounts of heat
over large distances.  The technology being tested by TEMP is
needed to meet the increased thermal control requirements of
space station.  The TEMP experiment will be the first
demonstration of a mechanically pumped two-phase ammonia
thermal control system in microgravity.  It also will
evaluate a propulsion-type fluid management reservoir in a
two-phase ammonia system, measure pressure drops in a two-
phase fluid line, evaluate the performance of a two-phase
cold plate design and measure heat transfer coefficients in a
two-phase boiler experiment.  EOIM-III/TEMP 2A-3 are
integrated together on a MPESS payload carrier in the payload
bay.


EOIM 111/TEMP 2A


CONSORTIUM FOR MATERIALS DEVELOPMENT IN SPACE COMPLEX
AUTONOMOUS PAYLOAD (CONCAP)

     The Consortium for Materials Development in Space
Complex Autonomous Payload (CONCAP) is sponsored by NASA's
Office of Commercial Programs (OCP).  On STS-46, two CONCAP
payloads (CONCAP-II and -III) will be flown in 5-foot
cylindrical GAS (Get Away Special) canisters.

     CONCAP-II is designed to study the changes that
materials undergo in low-Earth orbit.  This payload involves
two types of experiments to study the surface reactions
resulting from exposing materials to the atomic oxygen flow
experienced by the Space Shuttle in orbit.  The atomic oxygen
flux level also will be measured and recorded.  The first
experiment will expose different types of high temperature
superconducting thin films to the 5 electron volt atomic
oxygen flux to achieve improved properties.  Additional novel
aspects of this experiment are that a subset of the materials
samples will be heated to 320 degrees Celsius (the highest
temperature used in space), and that the material resistance
change of 24 samples will be measured on-orbit.

     For the second CONCAP-II experiment, the surface of
different passive materials will be exposed (at ambient and
elevated temperatures) to hyperthermal oxygen flow.  This
experiment will enable enhanced prediction of materials
degradation on spacecraft and solar power systems.  In
addition, this experiment will test oxidation-resistant
coatings and the production of surfaces for commercial use,
development of new materials based on energetic molecular
beam processing and development of an accurate data base on
materials reaction rates in orbit.

     CONCAP-III is designed to measure and record absolute
accelerations (microgravity levels) in one experiment and to
electroplate pure nickel metal and record the conditions
(temperature, voltage and current) during this process in
another experiment.  Items inside the orbiter experience
changes in acceleration when various forces are applied to
the orbiter, including thruster firing, crew motion and for
STS-46, tethered satellite operations.  By measuring absolute
accelerations, CONCAP-III can compare the measured force that
the orbiter undergoes during satellite operations with
theoretical calculations.  Also, during accelerations
measurements, CONCAP-III can gather accurate acceleration
data during the electroplating experiments.

     The second CONCAP-III experiment is an electroplating
experiment using pure nickel metal.  This experiment will
obtain samples for analysis as part of a study of
microgravity effects on electroplating.  Materials
electroplated in low gravity tend to have different
structures than materials electroplated on Earth.
Electroplating will be performed before and during the
tethered satellite deployment to study the differences that
occur for different levels of accelerations.

     The CONCAP-II and -III experiments are managed and
developed by the Consortium for Materials Development in
Space, a NASA Center for the Commercial Development of Space
at the University of Alabama in Huntsville (UAH).  Payload
integration and flight hardware management is handled by
NASA's Goddard Space Flight Center, Greenbelt, Md.

     Dr. John C. Gregory and Jan A. Bijvoet of UAH are
Principal investigator and payload manager, respectively, for
CONCAP-II.  For CONCAP-III, principal investigator for the
acceleration experiment is Bijvoet, principal investigator
for the electrodeposition (electroplating) is Dr. Clyde
Riley, also of UAH, and payload manager is George W. Maybee
of McDonnell Douglas Space Systems Co., Huntsville, Ala.


LIMITED DURATION SPACE ENVIRONMENT CANDIDATE MATERIALS
EXPOSURE (LDCE)

     The first of the Limited Duration Space Environment
Candidate Materials Exposure (LDCE) payload series is
sponsored by NASA's Office of Commercial Programs (OCP).  The
LDCE project on STS-46 represents an opportunity to evaluate
candidate space structure materials in low-Earth orbit.

     The objective of the project is to provide engineering
and scientific information to those involved in materials
selection and development for space systems and structures.
By exposing such materials to representative space
environments, an analytical model of the performance of these
materials in a space environment can be obtained.

     The LDCE payload consists of three separate experiments,
LDCE-1, -2 and -3, which will examine the reaction of 356
candidate materials to at least 40 hours exposure in low-
Earth orbit.  LDCE-1 and -2 will be housed in GAS (Get Away
Special) canisters with motorized door assemblies.  LDCE-3
will be located on the top of the GAS canister used for
CONCAP-III.  Each experiment has a 19.65-inch diameter
support disc with a 15.34-inch diameter section which
contains the candidate materials.  The support disc for LDCE-
3 will be continually exposed during the mission, whereas
LDCE-1 and -2 will be exposed only when the GAS canisters'
doors are opened by a crew member.  Other than opening and
closing the doors, LDCE payload operations are completely
passive.  The doors will be open once the Shuttle achieves
orbit and will be closed periodically during Shuttle
operations, such as water dumps, jet firings and changes in
attitude.

     Two primary commercial goals of the flight project are
to identify environmentally-stable structural materials to
support continued humanization and commercialization of the
space frontier and to establish a technology base to service
growing interest in space materials environmental stability.


LDCE


     The LDCE payload is managed and developed by the Center
for Materials on Space Structures, a NASA Center for the
Commercial Development of Space at Case Western Reserve
University (CWRU) in Cleveland.  Dr. John F. Wallace,
Director of Space Flight Programs at CWRU, is lead
Investigator.  Dawn Davis, also of CWRU, is program manager.


PITUITARY GROWTH HORMONE CELL FUNCTION (PHCF)

Principal Investigator:

Dr. W.C. Hymer
The Pennsylvania State University, University Park, Pa.

    The Pituitary Growth Hormone Cell Function (PHCF)
experiment is a middeck-locker rodent cell culture
experiment.  It continues the study of the influence of
microgravity on growth hormone secreted by cells isolated
from the brain's anterior pituitary gland.

    PHCF is designed to study whether the growth hormone-
producing cells of the pituitary gland have an internal
gravity sensor responsible for the decreased hormone release
observed following space flight.  This hormone plays an
important role in muscle metabolism and immune-cell function
as well as in the growth of children.  Growth hormone
production decreases with age.  The decline is thought to
play an important role in the aging process.

    The decreased production of biologically active growth
hormone seen during space flight could be a factor in the
loss of muscle and bone strength and the decreased immune
response observed in astronauts following space flight.  If
the two are linked, PHCF might identify mechanisms for
providing countermeasures for astronauts on long space
missions.  It also may lead to increased understanding of the
processes underlying human muscle degeneration as people age
on Earth.

    The PHCF experiment uses cultures of living rat
pituitary cells.  These preparations will be placed in 165
culture vials carried on the Shuttle's middeck in an
incubator.  After the flight, the cells will be cultured and
their growth hormone output assayed.


IMAX CARGO BAY CAMERA (ICBC)

     The IMAX Cargo Bay Camera (ICBC) is aboard STS-46 as
part of NASA's continuing collaboration with the Smithsonian
Institution in the production of films using the IMAX system.
This system, developed by IMAX Corp., Toronto, Canada, uses
specially-designed 70 mm film cameras and projectors to
produce very high definition motion picture images which,
accompanied by six channel high fidelity sound, are displayed
on screens up to ten times the size used in conventional
motion picture theaters.

     "The Dream is Alive" and "Blue Planet," earlier products
of this collaboration, have been enjoyed by millions of
people around the world.  On this flight, the camera will be
used primarily to cover the EURECA and Tether Satellite
operations, plus Earth scenes as circumstances permit.  The
footage will be used in a new film dealing with our use of
space to gain new knowledge of the universe and the future of
mankind in space.  Production of these films is sponsored by
the Lockheed Corporation.


AIR FORCE MAUI OPTICAL SYSTEM (AMOS)

     The Air Force Maui Optical System (AMOS) is an
electrical-optical facility located on the Hawaiian island of
Maui.  The facility tracks the orbiter as it flies over the
area and records signatures from thruster firings, water
dumps or the phenomena of shuttle glow, a well-documented
glowing effect around the shuttle caused by the interaction
of atomic oxygen with the spacecraft.

     The information obtained is used to calibrate the
infrared and optical sensors at the facility.  No hardware
onboard the shuttle is needed for the system.


ULTRAVIOLET PLUME EXPERIMENT

     The Ultraviolet Plume Experiment (UVPI) is an instrument
on the Low-Power Atmospheric Compensation Experiment (LACE)
satellite launched by the Strategic Defense Initiative
Organization in February 1990.  LACE is in a 43-degree
inclination orbit of 290 n.m.  Imagery of Columbia's engine
firings or attitude control system firings will be taken on a
non-interference basis by the UVPI whenever an opportunity is
available during the STS-46 mission.


STS-46 CREW BIOGRAPHIES

     Loren J. Shriver, 47, Col., USAF, will serve as
commander of STS-46.  Selected as an astronaut in January
1978, Shriver considers Paton, Iowa, his hometown and will be
making his third space flight.

     Shriver graduated from Paton Consolidated High School,
received a bachelor's in aeronautical engineering from the
Air Force Academy and received a master's in aeronautical
engineering from Purdue University.

     Shriver was pilot of STS-51C in January 1985, a
Department of Defense-dedicated shuttle flight.  He next flew
as commander of STS-31 in April 1990, the mission that
deployed the Hubble Space Telescope.  Shriver has logged more
than 194 hours in space.

     Andrew M. Allen, 36, Major, USMC, will serve as pilot.
Selected as an astronaut in June 1987, Allen was born in
Philadephia, Pa., and will be making his first space flight.

     Allen graduated from Archbishop Wood High School in
Warminster, Pa., in 1973 and received a bachelor's in
mechanical engineering from Villanova University in 1977.

     Allen was commissioned in the Marine Corps in 1977.
Following flight school, he was assigned to fly the F-4
Phantom at the Marine Corps Air Station in Beaufort, S.C.  He
graduated from the Navy Test Pilot School in 1987 and was a
test pilot under instruction at the time of his selection by
NASA.  He has logged more than 3,000 flying hours in more
than 30 different types of aircraft.

     Claude Nicollier, 47, will be Mission Specialist 1
(MS1).  Under an agreement between the European Space Agency
and NASA, he was selected as an astronaut in 1980.  Nicollier
was born in Vevey, Switzerland, and will be making his first
space flight.

     Nicollier graduated from Gymnase de Lausanne, Lausanne,
Switzerland, received a bachelor's in physics from the
University of Lausanne and received a master's in
astrophysics from the University of Geneva.

     In 1976, he accepted a fellowship at ESA's Space Science
Dept., working as a research scientist in various airborne
infrared astronomy programs.  In 1978, he was selected by ESA
as one of three payload specialist candidates for the
Spacelab-1 shuttle mission, training at NASA for 2 years as
an alternate.  In 1980, he began mission specialist training.
Nicollier graduated from the Empire Test Pilot School,
Boscombe Down, England, in 1988, and holds a commission as
Captain in the Swiss Air Force.  He has logged more than
4,300 hours flying time, 2,700 in jet aircraft.

      Marsha S. Ivins, 41, will be Mission Specialist 2
(MS2).  Selected as an astronaut in 1984, Ivins was born in
Baltimore, Md., and will be making her second space flight.

     Ivins graduated from Nether Providence High School,
Wallingford, Pa., and received a bachelor's in aerospace
engineering from the University of Colorado.

     Ivins joined NASA shortly after graduation and was
employed at the Johnson Space Center as an engineer in the
Crew Station Design Branch until 1980.  she was assigned as a
flight simulation engineer aboard the Shuttle Training
Aircraft and served as co-pilot of the NASA administrative
aircraft.

     She first flew on STS-32 in January 1990, a mission that
retrieved the Long Duration Exposure Facility (LDEF).  She
has logged more than 261 hours in space.

     Jeffrey A. Hoffman, 47, will be Mission Specialist 3
(MS3) and serve as Payload Commander.  Selected as an
astronaut in January 1978, Hoffman considers Scarsdale, N.Y.,
his hometown and will be making his third space flight.

     Hoffman graduated from Scarsdale High School, received a
bachelor's in astronomy from Amherst College, received a
doctorate in astrophysics from Harvard University and
received a master's in materials science from Rice
University.

     Hoffman first flew on STS-51D in April 1985, a mission
during which he performed a spacewalk in an attempt to rescue
a malfunctioning satellite.  He next flew on STS-35 in
December 1990, a mission carrying the ASTRO-1 astronomy
laboratory.

     Franklin R. Chang-Diaz will be Mission Specialist 4
(MS4).  Selected as an astronaut in May 1980, Chang-Diaz was
born in San Jose, Costa Rica, and will be making his third
space flight.

     Chang-Diaz graduated from Colegio De La Salle in San
Jose and from Hartford High School, Hartford, Ct.; received a
bachelor's in mechanical engineering from the University of
Connecticut and received a doctorate in applied physics from
the Massachusetts Institute of Technology.

     Chang-Diaz first flew on STS-61C in January 1986, a
mission that deployed the SATCOM KU satellite.  He next flew
on STS-34 in October 1989, the mission that deployed the
Galileo spacecraft to explore Jupiter.  Chang-Diaz has logged
more than 265 hours in space.

     Franco Malerba, 46, will serve as Payload Specialist 1
(PS1).  An Italian Space Agency payload specialist, Malerba
was born in Genoa, Italy, and will be making his first space
flight.

     Malerba graduated from Maturita classica in 1965,
received a bachelor's degree in electrical engineering from
the University of Genova in 1970 and received a doctorate in
physics from the University of Genova in 1974.

     From 1978-1980, he was a staff member of the ESA Space
Science Dept., working on the development and testing of an
experiment in space plasma physics carried aboard the first
shuttle Spacelab flight.  From 1980-1989, he has held various
technical and management positions with Digital Equipment
Corp. in Europe, most recently as senior telecommunications
consultant at the European Technical Center in France.
Malerba is a founding member of the Italian Space Society.



MISSION MANAGEMENT FOR STS-46

NASA HEADQUARTERS, WASHINGTON, D.C.

Office of Space Flight
Jeremiah W. Pearson III - Associate Administrator
Brian O'Connor - Deputy Associate Administrator
Tom Utsman - Director, Space Shuttle
Thomas D. Stewart TSS-1 Program Manager

Office of Space Science
Dr. Lennard A. Fisk - Associate Administrator, Office of
Space Science and Applications
Alphonso V. Diaz -  Deputy Associate Administrator, Office of
Space Science and Applications
George Withbroe - Director, Space Physics Division
R.J. Howard - TSS-1 Science Payload Program Manager

Office of Commercial Programs
John G. Mannix  - Assistant Administrator
Richard H. Ott - Director, Commercial Development Division
Garland C. Misener - Chief, Flight Requirements and Accommodations
Ana M. Villamil - Program Manager, Centers for the Commercial
  Development of Space Office of Safety and Mission Quality
Col. Federick Gregory - Associate Administrator
Dr. Charles Pellerin, Jr. - Deputy Associate Administrator
Richard  Perry - Director, Programs Assurance

KENNEDY SPACE CENTER, FLA.

Robert L. Crippen - Director
James A. "Gene" Thomas - Deputy Director
Jay F. Honeycutt - Director, Shuttle Management and Operations
Robert B. Sieck - Launch Director
Conrad G. Nagel - Atlantis Flow Director
J. Robert Lang - Director, Vehicle Engineering
Al J. Parrish - Director of Safety Reliability and Quality Assurance
John T. Conway - Director, Payload Management and Operations
P. Thomas Breakfield - Director, Shuttle Payload Operations
Joanne H. Morgan - Director, Payload Project Management
Robert W. Webster - STS-46 Payload Processing Manager


MARSHALL SPACE FLIGHT CENTER, HUNTSVILLE, ALA.

Thomas J. Lee - Director
Dr. J. Wayne Littles - Deputy Director
Harry G. Craft - Manager, Payload Projects Office
Billy Nunley - TSS-1 Mission Manager
Dr. Nobie Stone - TSS-1 Mission Scientist
Alexander A. McCool - Manager, Shuttle Projects Office
Dr. George McDonough - Director, Science and Engineering
James H. Ehl - Director, Safety and Mission Assurance
Otto Goetz - Manager, Space Shuttle Main Engine Project
Victor Keith Henson - Manager, Redesigned Solid    Rocket Motor Project
Cary H. Rutland - Manager, Solid Rocket Booster Project
Gerald C. Ladner - Manager, External Tank Project

JOHNSON SPACE CENTER, HOUSTON, TEX.

Paul J. Weitz - Director (Acting)
Paul J. Weitz - Deputy Director
Daniel Germany - Manager, Orbiter and GFE Projects
Donald R. Puddy - Director, Flight Crew Operations
Eugene F. Krantz - Director, Mission Operations
Henry O. Pohl - Director, Engineering
Charles S. Harlan - Director, Safety, Reliability and Quality Assurance

STENNIS SPACE CENTER, BAY ST. LOUIS, MISS.

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

AMES-DRYDEN FLIGHT RESEARCH FACILITY, EDWARDS, CALIF.

Kenneth J. Szalai - Director
T. G. Ayers - Deputy Director
James R. Phelps - Chief, Space Support Office

AMES RESEARCH CENTER, MOUNTAIN VIEW, CALIF.

Dr. Dale L. Compton     Director
Victor L. Peterson      Deputy Director
Dr. Steven A. Hawley    Associate Director
Dr. Joseph C. Sharp     Director, Space Research




                            - END -