Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/STATION/STFNOV90.NWS

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OCTOBER/NOVEMBER 1990 EDITION OF STATION BREAK.

Boiler Room Sessions Put Designers on Strict Diet, Hot Seat

        As summer's heat started to rise in June, Space Station
Freedom officials had two formidable tasks to hurdle -- to reduce
the station's weight, and to cut housekeeping power needs.
Although designers continue to weigh in each week, top officials
say this intense workout, now known as "boiler room" sessions,
made the station leaner.
        "The resources scrub has been a tremendous success story,"
said Marc Bensimon, deputy manager of the Space Station Freedom
Program and Operations Office in Reston, Va.
         "When we started this exercise, weight exceeded our
allocation by 143,546 pounds, and housekeeping power was 14.94
kilowatts (kW) over its allocation.  Since June, we have been
able to reduce the weight by 128,000 pounds and reduce the
housekeeping power by 12.5 kW, without impacting our objectives."

        So Freedom can launch its assembly components in 18 Space
Shuttle flights, its allocated weight is 512,000 pounds.  To
ensure that station users will have at least 30 kW of power,
housekeeping needs cannot exceed 45 kW.
        "We wanted to achieve these goals by being more efficient --
to take what we already have and make it leaner.  We wanted to
ensure that the station was being efficiently designed, and we
wanted to delete excessive requirements -- those that drive the
design but do not enhance capability," Bensimon said.
        During the summer-long scrubs, engineers were quizzed about
how and why they designed their assigned components the way they
did.  In any complex engineering project, such as the station or
the Shuttle, technical managers constantly challenge designers,
forcing them to search for better, more efficient ways to
accomplish tasks.
        Reviews such as these conducted during the hardware
development and mission phases of the Freedom program guarantee
the  integrity and success of the program, Bensimon said.
        While many of the intensive reviews took place at the
program office in Reston, Bensimon said the scrub's progress has
been program-wide.
        "The success didn't just happen in one place," he said.  "It
happened across-the-board -- here at Level 2 and at all the work
package centers and their contractors.  The whole program
contributed to this effort.  We also involved the users."
        None of the reduction decisions will adversely affect space
station science users, Bensimon said.  The station will provide
the 30 kilowatts of power, the volume, microgravity, and the
external mountings promised, he said.  In fact, Bensimon added,
"We've improved the external mountings by increasing the power at
each location from 3 kW to 6.2 kW and by adding active cooling."
        Though the review is already being termed a success, station
designers will continue trying to reduce weight and housekeeping
power, Bensimon said.
        "When we first started, I was optimistic, but I didn't think
we'd be able to get out 100,000 pounds without seriously hurting
program objectives.  We're close to our goal today, and program
objectives have remained intact.
        "Of course, in a review as quick and intense as this one has
been, you're bound to get some add back.  The trick is to get out
enough now so the add backs won't hurt too bad," Bensimon
stressed.
        Although this began as a NASA effort to streamline the
station, the international partners were invited and encouraged
to participate, Bensimon said.  The Canadian Space Agency, the
European Space Agency (ESA), and Japan's National Space
Development Agency, first wanted to see how NASA would approach
the problems, he said.
        "They saw the level of activity and the building momentum
and concluded they should conduct their own reviews," Bensimon
said.  Japan is now conducting its own effort; Canada conducted
both a power and weight scrub; and ESA, which is currently
coordinating its contractors, is using the information for
contract negotiations.
        Besides having the intended effect of reducing weight and
power requirements, this review also has contributed to lowering
the station's future operating costs, Bensimon said.
        "A lot of what was taken out was boxes," Bensimon said.  "By
taking out boxes, we've reduced what we'll have to maintain or
replace.  That directly reduces the life cycle cost.
        "We have simplified the architecture and design of the
station, so it will be less expensive to support the vehicle.  We
integrated the pieces.  Where we had three systems providing the
same type of services, we took those three pieces of equipment
and integrated them into one.  We took out excessive redundancy.
        "This exercise was good in all aspects," Bensimon said.
"The station is better technically, it fits resources more
closely, and it's better integrated."


Countdown Clock Ticks Toward Goals
        With the daily calendars of Space Station Freedom designers
flipping faster than ever toward the December preliminary design
review (PDR), the resource reduction exercises have greased the
wheels for a smoother integrated system review.
        "It's going to be a time to prepare for the integrated
system PDR in December, but resolving some of the issues during
the incremental PDRs and the resources exercises" means some
areas will be easier to work, said Marc Bensimon, deputy manager
for the Space Station Freedom Program and Operations Office in
Reston, Va.
        Both the resources scrub and the upcoming preliminary design
reviews are intended as checkpoints to keep the countdown clock
ticking toward the station's first element launch in March 1995.
        A countdown clock, which boldly displays foot-high red LED
numerals in the lobby of the  Reston building, is a constant
reminder to Bensimon that the program must keep pressing to reach
more mile-stones.  The clock, which started out at T-minus 60
months, now reads 53 months and counting.
        "When I come in every day and see that clock, and soon four
months have gone by, then five, it really makes you think,"
Bensimon said.  "I look at it every day and it makes me think --
I've got to keep this thing on the move."


Neutral Buoyancy Laboratory  to Provide  Assembly Testing

        It will weigh more than a billion pounds, have walls of
12-foot thick concrete, an 8-foot-thick bottom, and it will make
its inhabitants feel lighter than a feather.
        Workers will begin digging a 400,000-cubic-foot hole on the
grounds of Johnson Space Center in Houston in December as they
start construction of the Neutral Buoyancy Laboratory (NBL), a
facility that may be as crucial to the success of Space Station
Freedom as the launch pad.
        "The only way we can see that you can prove you can assemble
Space Station Freedom in orbit," said Vern Hammersley, chief of
the Man-Systems Division's Facilities Operations branch, "is to
do it in the water first."
        Simulating weightlessness on Earth in enough quantity to
practice assembling Freedom, or even a few parts of Freedom,
means thinking big.  And the NBL is a lesson in "large", said
Bill Roeh, the facility's project manager from the Facility
Development Division.   The pool will be 60 feet deep, 135 feet
wide and 235 feet long.    The building that will surround it
could hold a football field and one end zone, and its ceil-ing
will reach almost as high as a nine-story building, with a 10-ton
crane that can traverse its length.     "The size has been the
challenge," Roeh said. "Our design team has really enjoyed
working on all the unusual aspects of it.  It's been a set of new
frontiers and has expanded their engineering skills."
        The NBL will be completed in June 1993.  And it will be a
first-of-a-kind.
        Due to its 60-foot depth, astronauts will have to decompress
following a training session.  They will enter the pool from the
surface to begin training, but they will leave through an
underwater door in the side of the pool, 30 feet down.  The door
will lead to a more than three stories tall, 26-foot diameter,
solid stainless steel exit chamber, half-filled with water and
half-filled with a compressed atmosphere.  Astronauts will exit
the water there, doff their suits and then move through a common
air lock to either of two decompression chambers, both capable of
being used as medical facilities or as decompression and
debriefing areas.
        The decompression chambers are designed to take subjects to
a pressure equal to 160 feet underwater, a requirement for
treatment of decompression sickness, commonly called "the bends."

        "The exit changer permits us to decompress suited crewmen in
their shirt sleeves," Hammersley said.  "Without it, they would
have to make long decompression stops at certain depths on the
way up."
        Scuba divers won't have to decompress; they will rotate once
an hour.  And they'll breathe nitrox, a compressed air mixture of
about 40 percent oxygen, 60 percent nitrogen, instead of the
standard 20 percent oxygen, 80 percent nitrogen compressed air in
scuba tanks.  The oxygen-rich nitrox will provide an additional
safeguard against decompression sickness that can be caused by
frequent deep dives.
        The pool will be heated to 84 degrees, the optimum
temperature for diving safely.  Each of the 14 million gallons of
water will be filtered once every 24 hours, at a rate of 10,000
gallons per minute. The filters  will remove particles smaller
than human red blood cells.  A slower 1,000-gallon-per-minute
bank of filters will continually polish the polish the water,
removing particles as small as those that make up smoke.
        To build the NBL, 33 wells will be drilled 85 feet deep
around the perimeter of the building site, draining the water
table to a depth of 40 feet at the location.  The pool will be
built 30 feet below ground, 30 feet above ground.
        Because of the weight of the water as the pool is filled,
its sides and bottom are designed to flex as the structure
settles.  The pool may settle as much as two inches.  The sides
may bow outward as much as a half foot each.  The pool is
designed to flex, but the building surrounding it is not.
Special connections and expansion joints have been designed in
attachments between the two to allow for the pool's movement.
Also, two viewing windows will be in one side of the pool, 15
feet underwater.        An aircraft carrier-type cutaway in the deck
of the pool will allow mockups to be hoisted from a storage area
below the floor to the deck.  Four small cranes will be located
along the edges of the pool to lower astronauts or objects into
the water.
        The NBL is designed to allow multiple training activities to
be done at once.  For example, a Shuttle crew and a Freedom crew
can train underwater at different spots in the pool
simultaneously.
        A 32,000-square-foot wing on the building will house
offices, mechanical equipment, changing areas and technical
support areas.  A future wing on the opposite side of the
building is designed to accommodate a balcony viewing area 15
feet above the pool's deck.
        "The most exciting time for me will be when they're pouring
the concrete for the pool bottom and walls," Roeh said.  "And it
also will be the most critical."


Students Present Space Station Freedom Science Proposals

        Eleven national student winners in the 10th Annual Space
Science Student Involvement Program (SSIP) were recognized during
the National Space Science Symposium, in Oct. 1-3, in Washington,
D.C.
        The SSIP is cosponsored by NASA and the National Science
Teachers Association (NSTA) to stimulate interest in science and
technology by directly involving students in aerospace projects.
The SSIP competition involves more than a million students each
year in nine competition categories ranging from space science
experiments to arts contests to aerospace internships.
        On Oct. 1, eight national high school student winners
presented proposals for experiments, which theoretically could be
conducted on Space Station Freedom, to a panel of scientists and
educators at the Grand Hyatt Constitutional Ballroom.  Students
competed for scholarships and other awards.
        Winners in three other competition categories -- two winners
of newspaper competitions and the junior high school Moon Base
proposal winning team -- were honored during the National Space
Science Symposium.
        NASA Administrator Richard H. Truly lauded the students and
their efforts during a reception to honor the national winners
and their teachers.
        The following identifies the eight competing national
student finalists in the Space Station Competition and their
proposal topics, as well as three national winners in other
categories recognized.

PROPOSAL WINNERS
        Garen Thomas, Shoreham, N.Y., Topic:  "Studying Stresses in
Space."
        Peter S. Hahn, Northbrook, Ill., Topic:  "Caelogenesis: The
Redefinition of Evolutionary Theory in the Context of
Microgravity Experimentation."
        Amy R. Sigmon, Newton, N.C., Topic:  "The Effects of
Microgravity on the Tropisms of the Manducta Sexta."
        Trevor Haak, Sioux City, Iowa, Topic:  "Microgravity and Its
Effects on Ligin Concentration and Epinasty."
        Jihyun Oh, Lenexa, Kan., Topic:  "The Effects of
Tocophersdan on T-lymphocyte Proliferation in Microgravity."
        Nancy M. Martinez, Los Angeles, Calif., Topic:  "The Effects
of Space Environment on the Function of Male and Female Homo
Sapien Eyes."
        Sabbie Lail, Eagle, Idaho,  Topic:  "The Effects of Space
Environment on Movement, Transport and Concentration of
Indole-3-acetic Acid in the Vagna Radiata (Munga Bean)."
        Catherine Cusimano, Lansdale, Penn.,  Topic:  "The Effect of
a Boron Rich Diet on Bone Reduction in a Microgravity
Environment."

MOON BASE WINNER
        Wright Halbert and Michael Garza of Toppenish Middle School,
Toppenish, Wash., "Intrepid."

NEWSPAPER FEATURE AWARD WINNERS
        High School:  Heather Lee Fitzgerald, Wading River, N.Y.
        Junior High:  Julie Schwartzberg, Los Angeles, Calif.

 ADVERTISEMENT AWARD WINNERS
        High School:  Maria Carranza, Compton, Calif.
        Junior High:  Julie Schwartzberg, Los Angeles, Calif.


Studying the Invisible Milky Way
        There are billions of galaxies in the universe -- and
billions of stars in each galaxy.  Today, scientists believe that
each galaxy is a separate evolving entity that is constantly
changing.  Supernovas, nebulas, quasars, and other "energetic
phenomena" in the universe are believed to be galaxies or stars
in some stage of their life cycle.  Many of these energetic
phenomena produce a large quantity of X-rays.  These X-rays can
tell us much about the nature and origin of various celestial
objects, giving us vital clues about the nature and origin of our
own galaxy -- the Milky Way -- and solar system.
        Since the birth of X-ray astronomy in 1962, astronomers have
known about a diffuse glow of X-rays that emanate from all
directions in the sky.  The more energetic of these X-rays, those
with shorter wavelengths, are believed to originate from beyond
our Milky Way Galaxy.  However, in addition to the relatively
energetic  or "hard" X-ray background radiation, astronomers also
have discovered the existence of less energetic or "soft" X-ray
background emissions with characteristic longer wavelengths (in
the 10-100 Angstrom range).
        Observations performed with small, suborbital rockets have
revealed that, in contrast to the hard background radiation, this
soft X-ray radiation appears to emanate from within our galaxy.
In fact, a large fraction of this radiation appears to originate
from a region "close" to the Sun, perhaps within a few hundred
light years.  The observations also indicate that the source of
these X-rays is an extremely hot plasma that has a temperature of
about 1 million degrees Centigrade.
        A natural question follows: if this plasma does exist, where
did it come from, what was its source: A widely held theory is
that this plasma comes from a supernova that may have exploded
100,000 to a million years ago.  When a massive star dies, it may
end its life exploding as a supernova, throwing extremely hot,
fast-moving gas into the interstellar medium (the space between
the stars).  This gas quickly becomes highly ionized into a
"plasma" with temperatures of many millions of degrees.  As the
plasma expands, it cools and by the time it has traveled several
hundred light years its temperature has dropped to about a
million degrees, and the dominant emission is soft X-rays.  If
the Sun were inside such a region, the soft X-rays would appear
to be coming from all directions.
        To pinpoint the origin of the diffuse X-ray background,
scientists know that more precise measurements of the spectrum
are needed.  In particular, an instrument that could observe
emissions at specific wavelengths characteristic of atoms at a
temperature of one million degrees, could provide the necessary
information on the elements resonsible for the observed emission,
their temperature, and their ionization state.
        As part of NASA's continuing effort to determine the nature
and origin of this radiation, the Astro- physics Division of the
Office of Space Science and Applications (OSSA) has selected for
definition studies the X-Ray Background Survey Spectrometer
(XBSS) as a space station payload.  XBSS, scheduled for launch in
1997, is designed to perform precise spectral measurements of
soft X-ray background over the entire sky.  XBSS will expand on
the research to be started by the Diffuse X-Ray Spectrometer
(DXS), a Shuttle cargo bay experiment planned for launch in
mid-1992.  XBSS is a survey, as opposed to a pointed, instrument;
it will measure the spectrum by sweeping the sky above Freedom's
orbit, instead of being fixed in a certain direction.
        If XBSS observations confirm that the diffuse soft X-rays
are coming from an invisible ionized base, it will help verify
that supernova remnants produced the hot gas of the interstellar
medium.  This information will further the understanding of the
later stages of supernova remnant evolution and the role of a
supernova in the galactic life cycle.
        For more information about XBSS, contact Dr. Louis
Kaluzienski, Program Manager, Astrophysics Division,
[phone].


NASA Engineers Return to High School, Teach

        NASA computer programmers headed back to high school
recently -- this time to teach students how to use a
computer-aided training program for physics tutoring.
        Developed at Johnson Space Center (JSC) in Houston to train
astronauts and flight controllers, NASA's Technology Utilization
branch saw the artificial intelligence-based instruction program
as a way to boost students' interest in both physics and computer
technology.  This time-saving technology also will be used to
train crew aboard Space Station Freedom, so they can more quickly
perform indoor and outdoor maintenance tasks.
        "The Intelligent Tutoring System has fit rather well into
tutoring high school physics students," said Dean Glenn, JSC
technology utilization officer.  "It also can be used in other
subjects, such as  algebra, trigonometry, and chemistry."
        A similar interactive program also is being designed to
teach adults how to read.  The adult literacy program was
initiated by the Houston Read Commission, the U.S. Department of
Justice, and NASA.
        Since 1986, the Software Technology Branch at JSC and the
University of Houston-Downtown, with support from the Space
Station Advanced Development Program, and the Office of Space
Flight, have been actively developing intelligent computer-aided
training (ICAT) systems for use within NASA by astronauts, flight
controllers, and systems engineers.  This project is jointly
sponsored by NASA and the Apple Classroom of Tomorrow, a research
project of Apple Computer Inc., Cupertino, Calif.  The program's
focus is to develop a generic architecture for ICAT systems,
followed by the assembly of software environment to promote the
use of the generic architecture to specific training tasks.
        This version of the tutor program is designed to provide an
interaction between student and computer to solve physics
problems.  This student-computer interaction is intended to
foster a student's problem-solving skills and to help her or him
overcome the anxieties of learning a difficult subject.  The
program is designed to complement and enhance a teacher's
lectures and labs.
        "It's strength lies in its ability to continually observe
the student develop problem solutions and to intervene, when
appropriate, with assistance specifically directed at the
student's difficulty and tailored to the student's skill level
and learning style," said Dr. R. Bowen Loftin, professor of
physics at the University of Houston-Downtown.
        Student progress through the tutor is governed by the
student's own learning pace and style.  In addition, the
curriculum organization, symbols used, and problem repertoires
can be altered by the teacher to match that of his or her own
textbook and instruction strategy.
        Equipped with Apple MacIntosh II computers, teacher Beverly
Lee and the Physics I class of Clear Lake High School, League
City, Texas, are providing the classroom environment for test and
evaluation of the tutoring system, which isexpected to lead to
further refinements and expansion of its capabilities.  The
physics tutor lab takes an ordinary problem, applies it to a
physical situation, and then displays the problem, along with
computer illustrations of cars, buildings, etc., for the student
to solve.
        "My interaction with the students is more personal because
I'minteracting with two students instead of one," said Lee.
"Because the students are interacting with the computer, their
questions are very specific.   They are very interested in what I
have to say because they want to go on to the next step of the
program."
        One League City student, Belinda Wiggins, said of the
program, "The computer tells you if you make a mistake, so you
don't have to sit and wait on the teacher to tell you."
        Since the program was received well by both students and
teachers, Glenn says, NASA  eventually hopes to spin off the
techno-logy to private industry.


Scientists, NASA Slate Basic Lab Equipment
        Cooperative efforts have advanced the allocation of
Laboratory Support Equipment (LSE) system for Space Station
Freedom, says Dr. Robert J. Bayuzick, chairman of the Space
Science and Applications Advisory Subcommittee (SSSAAS).
        Through the collective efforts of the Requirement
Integration Group (RIG's) , the proposed lab equipment was
scrutinized and NASA determined what pieces are basic and
essential for station research.
        The initial list of proposed laboratory equipment was
assembled from "wish lists" submitted by researchers at NASA's
request.  Scientists were given no guidance or restrictions in
assembling their wish lists, said Bayuzick.  Having little
knowledge of what is involved in planning for research in space,
the researchers submitted lists of equipment similar to what they
would use to outfit their Earth-bound labs.  As plans for Freedom
developed, the wish lists were no longer applicable.  Members of
SSSAAS feared the proposed list would  unreasonably impact
available resources, like crew time and power, to support
long-term science on Freedom.
        The issue of equipment allocation was brought to NASA's
attention at the 1989 SSSAAS meeting in Woods Hole, Mass.  It
became increasingly difficult for NASA management to strike a
balance between the restrictions of space flight and the needs of
the researchers, Bayuzick said.  Responding to the concerns of
SSSAAS,  NASA assigned the task of reviewing and reevaluating the
lab equipment to RIGs.  The RIGs are comprised of NASA
representatives, contractors, and principal investigators
(scientists who will be sending research up in the space station
or Shuttle).
        The RIG's provided a forum for evaluation and review that
gave independent scientists, NASA, and contractors the
opportunity to communicate and work together.  Bayuzick said,
"Those  who took part worked intensely and spent considerable
time working   on the RIG's at the expense of other activities."
But, he said, "I would have liked for more of the scientific
community to participate."
        "Only those scientists who have made the decision to devote
their work to microgravity feel a responsibility for making the
system work and are willing to devote the time toward making it
work," said Bayuzick.  He commended the use of the RIGs and noted
that this cooperative effort is a landmark in NASA management.
The handful of scientists who have devoted their studies to
microgravity research consider it their responsibility to
represent the entire scientific community.  By doing this,
Bayuzick said, these researchers hope to open the microgravity
research gateway, so other scientists might be attracted to
space-based research.
        One area, researchers say NASA must control, is the
ever-escalating cost of hardware development.  Pieces estimated
to cost $10 million sometimes wind up costing $40 million.  This
continues to frustrate researchers, Bayuzick said.  Often,
scientists cannot afford to support such high markups, he
stressed.  However, Bayuzick said, recent working groups are
studying the situation to reduce costs and to improve the
development process.
        The reevaluation of the RIG's established more realistic
specifications for individual pieces.   Based on the RIGs
recommendations, Office of Space Flight officials decided what
equipment could be deferred.  Deferred items are important but
not essential to the maintenance of a lab in space.
        There were 23 pieces of equipment selected to establish a
sound research foundation for Freedom.  Much of this equipment is
common to all experiments, such as a refrigerator, pH meter,
digital thermome-ter, and hand tools. These items are now
considered "core LSE" and will be provided by the Freedom
program.  The remaining 21 items will continue to be evaluated as
"non-core LSE".   In evaluating and upgrading some pieces of
equipment based upon the RIG's recommendations, NASA has
developed a set of equipment that will support the use of
Freedom's lab for years to come.
        The groups scrutinized every piece of proposed hardware and
evaluated it according to its function, design, and cost.  Pieces
were altered or eliminated  based upon the practicality of their
function.  An important outcome of the RIGs meeting is the
"commitment made to analyze the lab equipment on a periodic basis
to ensure that it is not outdated by the time Freedom is fully
operational," Bayuzick stressed.


Space Station's Annual Science Use Review Held
        The Science Utilization Management (SUM) annual program
review, recently held at NASA Headquarters, symbolized a
milestone in achievement for the scientific use of Space Station
Freedom.  The review was the first held since the release of the
OSSA Payload Traffic Model in September 1989, which formalized
the planned space station payloads and their respective launch
dates.
        The review covered numerous issues of current concern to the
science community.  Participants discussed Spacelab transition
studies now under way; information systems planning status;
operations and training requirements, plans, and facilities;
station-induced contamination issues; pointing system studies;
and safety, reliability, and quality assurance issues.
        The SUM team is a key element of OSSA's overall science
utilization strategy for Freedom.  The team is comprised of
representatives from NASA field centers and provides management
coordination within OSSA and between OSSA and the Freedom
program.