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JANUARY 1991 STATION BREAK NEWSLETTER

Augustine Report Reflects NASA's Actions

        Although Space Station Freedom's restructure assessment will bring few
concrete changes before January's end, the three-month assessment gave NASA a
jump start on implementing the recommendations of a blue-panel study, said Dr.
William B. Lenoir, Office of Space Flight associate administrator.

        In essence, Lenoir said, the Presidential Advisory Committee on the
Future of the U.S. Space Program, also known as the Augustine Committee, told
NASA to lessen the complexity and cost of Freedom, a task station managers have
been working on feverishly since December.

        "The only difference between what we have said and what they are
telling us is that we place a slightly higher priority on microgravity
research than they do," Lenoir said.

        Space Station Freedom remains a critical and integral part of the U.S.
space program, the Augustine Committee said, because learning more about how
the human body operates in space is essential for human space exploration.

        "We do not believe that the Space Station Freedom, as we know it, can
be justified solely on the basis of the (nonbiological) science it can
perform, much of which can be conducted on Earth or by robotic spacecraft for
less cost," the committee said in the report. "Similarly, we doubt that the
space station will be essential as a transportation node -- certainly not for
many years.

        "However, the space station is deemed essential as a life sciences
laboratory, for there is simply no Earth-bound substitute .  The space station
is a critical next step if the U.S. is to have a manned space program in the
future.  At the same time, the space station can provide a capability for
important microgravity research, and for practical experience in manufacturing
under low-gravity conditions," the committee said.

        "Given these conclusions, we believe the justifying objectives of the
Space Station Freedom should be reduced to two: primarily life sciences, and
secondarily microgravity experimentation.  In turn, we believe the Space
Station Freedom can be simplified, reduced in cost, and constructed on a more
evolutionary, modular basis that enables end-to-end testing of most systems
prior to launch, and reduces extravehicular flight requirements along the
lines NASA is now considering."

        One step station managers have already taken to reduce cost,
complexity, and extravehicular activities is to shorten the habitation and
laboratory modules, Lenoir said.

        "Since we're still in the middle of our work, I can't talk too much
about what's going on, but I can tell you that we do plan to go with shorter
modules," Lenoir said.

        Before budgetary constraints and a congressional mandate forced station
managers to begin the space station restructure assessment, the two modules
were designed to be 44 feet long.  Now station managers are planning to trim
that size to about 27 feet long , and eventually the program plans to send up
four modules to increase living and research space, Lenoir said.

        "We decided to shorten the modules so we can stuff them and send them
up full, rather than launch empty and stuff them in orbit," Lenoir said. "This
will save risk because we don't have a lot of experience with on-orbit
integration.  It also will save crew time, so they can make observations and do
experimentation, rather than build hardware," Lenoir said.

        Another option designers are researching is moving toward a
preintegrated truss, "so we don't have to build it one stick at a time.  It may
not pass muster, but we're reviewing it," Lenoir said.

        Program managers still are trying to delete content, and move hardware
around in an attempt to stay near the first element launch time frame of March
1995, although that date is looking less likely, Lenoir said.

        "We've got all of the options on the table, and we're picking and
choosing, mixing and matching, trying to put things together.  Right now, we
think it will probably look similar to the station we have today, but it will
be smaller and somewhat less capable.  We continue to work toward a phased
approach," which is in line with the Augustine recommendations, Lenoir said.

        "It will be after the first of January before the design begins to gel,
and then it will probably take another month beyond that to sand some of the
rough edges," he said.

        Meanwhile, Space Station Freedom managers last month wound up the
program's Integrated System Preliminary Design Review (ISP DR) , an exercise
that analyzed the acceptability of Freedom's integrated design.

        The ISPDR, which culminated at a Dec. 20 board meeting at Level II in
Reston, Va., took precedence over the restructure assessment, because any
structure deviation must come from the ISPDR baseline, said Space Station
Freedom Director Richard Kohrs.

        "We are not going to start over," Kohrs said. "We are going to work as
much as possible with the existing development."

        Hundreds of Freedom engineers and designers leafed through thousands of
pages of documentation to analyze the acceptability of Freedom's integrated
design.

        Goals for the ISPDR were to ensure that the design actually reflects
the program's requirements; to verify the safety and operational adequacy of
the integrated design; to confirm the compatibility of the physical and
functional relationships; and to assess the preliminary design for its ability
to be produced, integrated, and verified.

        The ISPDR's requirements review also updated program requirements for
stage content and milestones.

        Reviews such as this are conducted during the hardware development and
 mission phases to guarantee the integrity and program success, Kohrs said.





NASA Slates Freedom Test Flights on Space Shuttle Fleet



        Within the next two years, Space Station Freedom designers expect to
 fly at least three experiments aboard the Space Shuttle fleet.

        This April, astronauts will float out of Space Shuttle Atlantis'
 airlock, 243 nautical miles above Earth, for the first NASA space walk in more
 than five years.

        After the Gamma Ray Observatory is lofted into space, astronauts will
perform an extravehicular activity, or space walk, to find the best ways to
construct Space Station Freedom's truss on orbit, Dr. William B. Lenoir said at
a December press briefing.  The next Freedom experiment to fly aboard the
Shuttle Discovery in July will be the Space Station Advanced Heat-pipe Radiator
Element II (SHARE II), which is the station's cooling system.  This flight
test will assess the heat-pipe's improved design, Lenoir said.  The first
generation SHARE flew on the side of Discovery's cargo bay in April 1989.

        Once engineers gathered all of the in-flight data, they were able to
pinpoint what they think caused the original SHARE to operate only
sporadically during its flight test.  With that knowledge, Lenoir said, they
were able to modify SHARE's design so it will work properly.

        "We think we've got the problem corrected, so now we want to check it
out in flight," Lenoir said.

        In May 1992, a year after the new orbiter, Endeavour, is unveiled,
engineers will test the Crew Equipment Transfer Aid (CETA), which will
transport astronauts during space walks along the station's length, Lenoir
said.  During that flight, he said, NASA plans to test the astronauts'
capability of completing three consecutive space walks with three different
space walk teams of two.





Lunar Lettuce Update: The Tomatoes Did It



        SUNNYVALE, November 15, 1990 -- The company that gave the world "lunar
lettuce" has added "cosmic carrots" and "extraterrestrial tomatoes" to its
garden -- and is giving space mystery buffs plenty to chew on.

        The tomatoes are the culprits.  They're killing off the lettuce, and
researchers at Lockheed Missiles & Space Company want to know why.

        It's a clear case of cosmic vegicide.

        Dr.  Steven Schwartzkopf is the chief scientist and space farmer in
this ambitious gardening experiment.  He hopes his work eventually will
provide fresh produce for veggie-hungry astronauts and planetary explorers.
His research team began last year by investigating hydroponic lettuce.  They
grew the plants in a water-based solution to test several nutrient systems.

        The results were excellent. "We found that we could grow the lettuce
two or three times faster in hydroponics than in soil, " Schwartzkopf reported.

        The team then began experimenting with polycultures, to see which
plants would grow well together.  The first combo: lettuce and tomatoes.  One
experiment ran three lettuce harvests consecutively in the same nutrient
solution as one crop of tomatoes.  The tomatoes thrived, but the lettuce did
not fare so well. "The first crop did fine," Schwartzkopf said, "but the second
showed inhibited growth, and the third was even worse."

        Schwartzkopf says the tomatoes definitely are the villains.  They are
either taking in too much of a nutrient that the lettuce needs, or putting out
a toxic substance that is killing it.

        "In either case," he said, "we're on to something here, and solving the
 mystery will make a good contribution to agriculture -- on Earth and away from
 it." The research is giving space scientists valuable information on
 companion-planting, which will enable them someday to produce food crops on
 Space Station Freedom, the Moon and Mars. That some plants are compatible and
 others aren't is nothing new.  With trial and error, most backyard gardeners
 learn which species get along with each other and which don't.

        "What we don't know is why," Schwartzkopf said, "and we need to find
out so we can manage crops efficiently when we move to distant planets.  Trial
and error isn't good enough in space."

        Reliable, quantitative data on plant polyculture will not only benefit
 space gardeners, he claims, but perhaps could produce larger crop yields and
 better disease control here on Earth. "We hope to learn the best
 combinations," he said. "Maybe we'll find species that actually protect other
 plants or even improve their growth."

        At Lockheed, investigation into the tomato mystery continues.  Next on
the agenda: some fancy detective work on the deceased veggies.  As each crop
was cultivated, the team dried and saved the plants.  They are now analyzing
the lettuce to learn why it died and perhaps find a way to protect future
crops. "This is like an episode of 'Columbo,'" Schwartzkopf said. "We know the
tomatoes did it, but we have to figure out how." "The Case of the Killer
Tomatoes" is just one of the dramas unfolding in Schwartzkopf's lab.  The
researchers also are trying to learn why their hydroponic carrots look so
funny.

        "The idea of growing carrots in water instead of soil was challenging,"
 Schwartzkopf said. "Would they grow at all?  If so, would they look like
 carrots or, without soil and the force of gravity, would they take on some
 strange shape?"

        The answers: "Yes and yes -- sort of." The carrots do grow in water.
To date, the team has tested six varieties, with mixed results.

        "Three did well, one was fair, and two didn't do well at all,"
Schwartzkopf reported, "and the plants that grew did look like carrots -- with
a twist.  The tops of the plants grew normally, but the roots tended to curl
up.  We don't know why yet.  Maybe it was the motion of the nutrient solution
or maybe the lack of soil.  Whatever the cause, they have that funny curve."

        "Who knows?" he joked, "Maybe in space, with little gravity, these
things will grow into salad-ready carrot curls.  In any event, they taste
great!"





A Garden in Space



        The average person consumes approximately a pound of food,
three-quarters of a gallon of water, and over 800 liters of oxygen per day.
These provisions are not available in the barren environment of space and so
must be stored in the cramped quarters of a spacecraft.  So far in the manned
space program, life-support systems have relied on a sufficient storage of
food, water, and oxygen placed aboard the spacecraft before launch.  Waste
products have to be stored for return to Earth. Storing food has worked for
short-term visits to space such as Shuttle missions.  However, putting man on
the Moon and Mars will require a system that can operate for very long periods
of time without a resupply from Earth, one that can grow food and recycle
waste.

        A life-support system based on recycling can be based on physical and
chemical processes, can be biological in nature, or can be a combination of
both.  Chemical systems are more easily designed than biological systems, but
provide little flexibility or adaptability to changing needs.  A life-support
system based solely on physical and chemical methods would also be limited
because it would still require resupply of food and some means of waste
disposal.

        A bioregenerative life-support system incorporates biological
components in the creation, purification, and renewal of life-support
elements.  Plants and algae are used in food production, water purification,
and oxygen release.  But, while the interactions of the biomass with the
environment are very complex and dynamic, creating a fully closed ecological
system--one that needs no resupply-- is possible.  Life scientists have called
a system involving a combination of chemical and biological processes a
Controlled Ecological Life Support System (CELSS).

        The CELSS Flight Program is designed to meet the science community's
requirement for extended duration space research.  Sponsored by the Life
Sciences Division in the Office of Space Science and Applications, the program
is part of the division's plan for biological research on Space Station
Freedom: the Space Biology Initiative.

        Like many pressurized experiments to be flown on the space station, the
CELSS Test Facility will use hardware concepts that have first flown on the
Space Shuttle.

        The four "precursor" flight tests on the Shuttle are the Nutrient
Delivery  Systems Test and Evaluation (NDS), Gas/Liquid Interaction Tests
(GLI), Water Condensation and Re-cycling Tests (CRS), and Germination Screening
(ROOT).  The NDS is designed to test how well selected nutrient delivery
systems operate in a low-gravity environment.  The objective of the GLI is to
identify potential problems in a plant's fluid management system in low
gravity, since it is essential to provide plants with enough surface area for
gas exch ange without limiting access to nutrients.  The CRS will evaluate
water condensation, collection, and recycling technologies in a plant growth
system.  Finally, ROOT will look at issues involving the germination and
sprouting process in young plants.

       The purpose of the CELSS Test Facility (CTF) on Space Station Freedom
is to provide NASA with a test bed to develop advanced life-support systems
based on biological systems.  Occupying two space station racks, the CTF will
be composed of a plant growth chamber about the size of an average closet.
The long on-orbit time gives scientists the capability to study plant
populations throughout complete life cycles and over many generations in a
controlled microgravity environment.  All of the monitoring and environmental
control of the experiment will be fully automated, including a robotic arm for
specimen handling.

        CTF results will be used to identify candidate crops for future CELSS,
to determine how well the experiment's subsystems work, and to pinpoint plant
growth techniques that yield the highest quality and quantity of crops.  The
CTF's experiments will determine the best combinations of environmental
factors such as lighting, humidity, temperature, and plant growth area.  The
amount of plant growth area needed is particularly important given the limited
quarters on the station.

        Developing CELSS technologies will have significant benefits on Earth.
The knowledge gained from these intensive plant growth studies will lead to
better methods of growing terrestrial crops.  Using the strides gained in CELSS
research, humans may be able to live for even longer periods of time in harsh
climates such as the Antarctic. Studying the carbon dioxide/oxygen and water
cycles in the controlled environment of the space station will lead to a
better understanding of these cycles as they operate regionally or globally on
Earth. The technology developed to support CELSS will also be applicable in
urban areas to improve techniques of wa ter purification and waste processing.

        Because it will take many years of research to create a system in space
that imitates--at least in some degree--the way biological cycles work on
Earth, the development and testing of CELSS technologies need to begin now.  We
need to begin now to support the advanced mission of the future, missions that
may take man to the Moon, Mars, and beyond.



International Science Forum Meets in Rome



        The International Forum for the Scientific Uses of the Space Station
(IFSUSS) met in Rome, Italy, in October 1-4, 1990, to discuss and explore
international science opportunities and concerns.  The first two days of the
forum included scientific discussions on topics such as exobiology, protein
crystal growth, Earth observations, and space plasma science.  The last two
days of the forum were devoted to general discussions and developing
recommendations, which were subsequently delivered to the Office of Space
Science and Applications' Space Station Science and Applications Advisory
Subcommittee meeting, Nov. 28-30, 1990.

        The four principal recommendations generated at the meeting covered a
broad range of current user concerns.  The first recommendation resulted from
a consensus that there is a need for a more formal mechanism for international
science community input to sp ace station science planning and operations.  The
proposal recommended the creation of International Science Working Groups
(ISWGs) formed in three discipline areas: Life Sciences; Materials, Fluids, and
Combustion Sciences; and Observing and Sensing Sciences. These science working
groups would become the "work horses" of the Forum.

        The second recommendation was that payload operations be conducted with
a discipline rather than a national focus to maximize the scientific return
from the space station.  The intent of this recommendation is to organize and
electronically link investigators together by science discipline so that the
first line of scientific input on payload operations during the execution phase
is made within disciplines at the investigator level.

        While applauding the significance of the March 1990 Tokyo agreement on
 standardizing the experiment racks, the third IFSUSS recommendation stated
 that the agreement should be broadened so that most of payloads can be
 accommodated within all laboratory modules.  The final recommendation
 emphasized the importance of the attached payloads in the overall successful
 utilization of the space station.  IFSUSS is concerned about the "perceived
 softening in support" for attached payloads by all partner agencies,
 especially NASA. The recommendation encouraged the Space Station Freedom
 program to continue to support selected attached payloads, and suggested that
 any future budget considerations regarding this program be made only after
 consultation with the international science participants.

        IFSUSS is comprised of members of the four space station partner
science advisory committees: NASA's Space Station Science and Applications
Advisory Subcommittee, ESA's Space Station User Panel, the Japanese Science
Advisory Group, and the Canadian Advisory Committee on the Uses of Space
Station. The group is dedicated to the goal of enhancing the quality of
international science that can be conducted on the space station.

        The nature and emphasis of IFSUSS has evolved over the years from a
predominantly scientific meeting to one including partner agency
representatives, addressing a broad range of utilization topics and
programmatic issues directly affecting science users.  IFSUSS meetings are held
twice yearly.  One meeting continues the focus on scientific issues,
encompassing all disciplines involved in the utilization of the station and is
conducted as a workshop to address science issues.  The other predominantly
emphasizes accommodations and resources provided by the space station, its
configuration, evolution, and planned research programs.

        IFSUSS serves to promote cooperative and collaborative science
utilization planning at the international level to identify requirements for
hardware commonality and to propose strategies for small and rap-id response
payloads.  Its value lies in its providing an arena for the input of
experienced space scientists, enriched by international experience,
unencumbered by formal program responsibilities, and independent of the
partners.

        IFSUSS has become a sounding board for the evaluation of new ideas
about station operations, planning, future development, and management.  It
represents a resource for the station partner agencies to use to obtain
information on the needs and aspirations of the international space community.
This input helps science program offices determine appropriate utilization of
the station, and in guiding station design and development in a manner
consistent with broad scientific utilization.

        The next IFSUSS meeting will be hosted by ESA the week of May 6, 1991.
For more information on IFSUSS, call Bob Rhome, Assistant Associate
Administrator for Space Science and Applications, [phone].





  Space Station Freedom Passes First Vacuum System Test



        As a major subcontractor to Boeing Aerospace & Electronics on the Space
Station Freedom program, Teledyne Brown Engineering is well into the design of
several U.S. Laboratory module systems.

        One of these is the vacuum system, which allows experiments access to
the vacuum of space.

        This vacuum service is designed to be routed throughout the laboratory
module, serving 22 user experiment facilities.  As part of the design process,
several tests will be conducted on prototype components of the vacuum system.

        These tests check out various design concepts and gather data needed to
perform design calculations.  The first test conducted on vacuum system
components was completed on July 25.  This test was designed to determine if
the structural integrity and perfor mance of the vacuum system piping
connections would be affected by the shuttle liftoff vibration environment.

        An 18-inch shaker table at NASA's Marshall Space Flight Center in
Huntsville was used to simulate vibrations of shuttle lift off for the flanges
(pipe connections) of the vacuum system.

        It was the first test of its kind for the vacuum system, and TBE
engineers were pleased that the test sample was not adversely affected by the
liftoff simulation.

        Each flange connection is sealed with a "c" ring made of gold-coated
inconel (a high-nickel alloy).  Two types of clamps designed to hold the
flanges together were tested in this liftoff simulation.  These included a
steel ring clamp (or marmon clamp) and a stainless steel chain clamp that
surrounded the flange and was tightened at the top by a screw.  Both types of
flange connections passed the liftoff simulation test by maintaining their
structural integrity and performance.  The actual acceleration levels induced
by the vibrations were as high as 140 g's, or 140 times the normal force of
gravity.  Varying levels of vibrations were applied to simulate environments
in the module utility runs and end cones during shuttle liftoff.

        Helium was pumped inside the two pipe sections.  A leak test was
conducted by TBE technicians between each 90-second application of the liftoff
scenario.  Boeing personnel were on hand to measure stresses in the pipe
section caused by the vibrations.  These data were collected by a series of
sensors, called strain gauges, attached to the test sample.

        TBE engineer Jim Shepherd labeled the test a success because it showed
that the vacuum piping was not structurally damaged when faced with the
vibration forces of liftoff, and no loss in vacuum level occurred.





Flight Telerobotic Servicer Industrial Briefing Deemed a Success



        To meet a congressional directive that the Flight Telerobotic Servicer
(FTS) program should enhance United States expertise in the fields of
automation and robotics, and thereby contribute to the nation's economic
competitive advantage, NASA and Martin Marietta held a three-day FTS
Industrial Briefing in December in Denver, Colo.

        Some 79 individuals attended including 18 NASA and Martin Marietta
 personnel.  The 61 people seeking information represented more than 40
 organizations, including large corporations, smaller companies, other
 government agencies, and universities.

        The afternoon of the first day featured a tour of the Martin Marietta
facility, nestled in the foothills of the Rocky Mountains.  The tour focused
on the robotics lab, simulators, computer facilities, and clean rooms, where
the robots are assembled and tested.  On the second day, a variety of speakers
from NASA, Martin Marietta and several subcontractors briefed participants.
The detailed presentations covered a full range of subjects. "The briefing
exceeded our expectations," says Kevin Barquinero, Space Station Freedom
program, NASA Headquarters. "The event was very well attended and the
participants were pleased with the information they received."

        Companies were free to set up confidential "one-to-one" discussions
with Martin Marietta personnel on the third day of the conference, so subjects
of particular interest could be pursued.  K. Z. Bradfordof Martin Marietta said
several companies did opt for these private follow-up sessions.