Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/DAILY_1/930217.DFC

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17-Feb-93 Daily File Collection
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2/17/93:  NASA STUDY MAY HELP REDUCE LIGHTHEADEDNESS AFTER SPACE FLIGHT

Michael Braukus
Headquarters, Washington, D.C.                  February 17, 1993

Jane Hutchison
Ames Research Center, Mountain View, Calif.



RELEASE:  93-030

     A study at NASA's Ames Research Center, Mountain View, Calif., may lead to
improved ways of keeping astronauts from feeling faint when they stand after
returning to Earth from space.

     Dr.  Joan Vernikos, the study's principal investigator, said a reduced
level of plasma is believed to contribute to this tendency to feel faint.
Plasma is the fluid part of the blood, without blood cells.

     "The primary purpose of this study is to compare the effectiveness of two
procedures that expand plasma volume," said Vernikos, Chief of Ames' Life
Science Division.

     "We long have known that expanded plasma volume may be a key to preventing
fainting in people following head-down bed rest and potentially, in
astronauts," she said.  Bed rest in a slightly head-down position simulates
many of the physiological effects of weightlessness.

     Vernikos said that without the pull of Earth's gravity, astronauts
experience an upward shift of body fluids.  The body responds to what it
perceives as excess fluid and reduces the amount of circulating fluid volume by
excreting more urine.

     Upon return to the normal gravity of Earth, fluids again shift to the
lower extremities.  This increases the chance an astronaut will feel
lightheaded immediately after landing, she said.

     By finding reliable and acceptable means of increasing the plasma volume
in volunteers, Vernikos believes much of this light-headedness can be
prevented.

     Space Shuttle crews routinely take water and salt tablets just before
re-entry.  Vernikos said this is believed to expand plasma volume in astronauts
in space, but it has never been measured.

     "We don't know by how much and for how long the expansion of plasma lasts,
especially in the weightless state when the body's normal response is to
excrete excess fluid," she said.

     "We also have had promising results with a synthetic steroid similar to
steroids normally found in the body," Vernikos said.  This steroid, which
produces the same effect as the salt tablets and water, may provide a more
reliable alternative, particularly as mission lengths increase.  It is used
clinically to treat people who faint or experience sudden bouts of low blood
pressure when they stand, she said.

     Her study involves six women and six men ages 30 to 50.  Plasma volume is
measured in each person under three conditions: after taking water and salt
tablets, after taking the synthetic steroid or after no medication.

     Two hours after each treatment, the volunteer lies quietly for 30 minutes.
A blood sample is drawn and a dye is injected into the volunteer, then a second
sample is drawn for the measurement of plasma volume.  The volunteer then
stands for 15 minutes and additional blood samples are drawn 5 and 15 minutes
after standing.  Blood samples will be used to measure the hormones that
regulate sodium and fluids.  Blood pressure and heart rate responses to
standing also are measured.

     The study will add to the limited data about how women adapt to space
flight.  Although women also serve as astronauts, data from flight and
ground-based simulation studies are derived almost exclusively from men,
Vernikos said. "The very few studies that have included women suggest that they
tolerate and adapt to head-down bedrest as well as men," she said.

     Responses to the treatments may vary not only by sex, but also with the
time of day, she added.  Vernikos will measure the effectiveness of both
treatments during the day and at night. "Our purpose is to find the most
effective treatment and the minimum effective dose, with the least side
effects, for both sexes," she said. "It is very important that we have this
information before we test drugs of any kind on astronauts in space."

     Previous studies have shown that all people with a tendency to faint have
some common characteristics, Vernikos said.  These include a higher plasma
volume under everyday resting conditions.  In addition, various hormones that
constrict blood vessels and raise blood pressure when the person stands up are
less effective in fainters.  After bedrest or space flight, these
characteristics are aggravated.  Besides expanding plasma volume, the steroid
also may boost these mechanisms.

     Drs.  Mary F. Dallman and Lanny Keil of the University of California, San
Francisco, are co-investigators.  Dee O'Hara, Manager of Ames' Human Research
Facility, is coordinating the study.
     Source:NASA Spacelink    Modem:205-895-0028  Internet:192.149.89.61
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=--=--=START=--=--= NASA Spacelink File Name:930217.SHU

KSC SHUTTLE STATUS 2/17/93


              SPACE SHUTTLE WEEKLY STATUS SUMMARY
                   Wednesday, February 17, 1993


George H. Diller
Kennedy Space Center


Vehicle: OV-102/Orbiter Columbia    Mission: STS-55
Current location: Pad 39-A          Orbital altitude: 184 sm
Payloads: Spacelab D-2/SAREX        Inclination: 28.45 degrees
Launch timeframe: March wk 2        Nominal Landing: KSC
Mission Duration: 8 days 22 hours   Crew size: 7


STS-55 IN WORK:

- hoisting engine #2 turbopump to aft main engine compartment
- turbopump inspections in VAB main engine maintenance facility
- troubleshooting main engine #2 hydraulic yaw actuator
- inspection of main engine heat shields
- crew compartment cleaning


STS-55 WORK SCHEDULED:

- lower main engine #3 liquid oxygen turbopump tonight
- hoist main engine #3 liquid oxygen turbopump Thursday
- install new orbiter refrigerator/freezer units next Tuesday


STS-55 WORK COMPLETED:

- removal of main engine #2 high pressure liquid oxygen turbopump
- installation of main engine #1 high pressure liquid oxygen turbopump


NOTES:
     Changeout of Columbia's main engine liquid oxygen turbopumps is running
somewhat ahead of schedule today.  The two pumps which were removed from the
main engines have been examined and, as was expected, the correct seal
retainers are installed.
     Source:NASA Spacelink    Modem:205-895-0028  Internet:192.149.89.61
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=--=--=START=--=--= NASA Spacelink File Name:930217.SKD

DAILY NEWS/TV SKED 2/17/93

Daily News
Wednesday, February 17, 1993
Two Independence Square,
Washington, D.C.
Audio service: 202/358-3014

 % Kennedy technicians on schedule for Columbia pump change-outs;
 % JPL reports Ulysses entered safe mode; recovered nominally;
 % Stennis continues with visitor and education programs.

* * * * * * * * * * * * * * * *

Kennedy Space Center technicians have removed the liquid oxygen turbopump from
Columbia's #1 main engine and are in the process of removing the pump from
engine #2.  The changeout of turbopumps is proceeding well.  Office of Space
Flight management expects to schedule a new target launch date sometime next
week.

* * * * * * * * * * * * * * * *

Jet Propulsion Laboratory flight controllers report the Ulysses spacecraft went
into an automatic safe mode this past Sunday while it was being tracked through
the Madrid Deep Space Network station.  Ulysses' onboard systems shut down and
the telemetry stream ceased.  The spacecraft was reacquired about 5 hours and
10 minutes later through the Goldstone station.  Following reacquisition, JPL
engineers went through a series of health checks and affirmed that Ulysses was
in good shape and had configured itself properly following the outage.  All but
one of the nine instruments was expected to be back on-line by today.  The sole
remaining inactive instrument is the Solar Wind Ion Composition experiment
which requires additional warm-up time because of high voltage power supplies.

Ulysses is about 379 million miles (610 million kilometers) from Earth and is
18 degrees below the Plane of the Ecliptic. It is moving southward at a speed
of 22,000 miles per hour (35,000 km/h) relative to the Sun. One-way light time
is 38 minutes.

* * * * * * * * * * * * * * * *

Stennis Space Center conducted their Early Education Monday program for 288
kindergarten children from seven Mississippi and Louisiana schools this past
week.  The center also toured 1,419 visitors from 38 states and 10 foreign
countries.  Eighty of the visitors were able to witness an engine test firing
during their tour.

* * * * * * * * * * * * * * * *

Here's the broadcast schedule for Public Affairs events on NASA Select TV. Note
that all events and times may change without notice, and that all times listed
are Eastern. Live indicates a program is transmitted live.

Wednesday, February 17, 1993

STS-57 Spacehab mission simulation - no scheduled programming.


NASA Select TV is carried on GE Satcom F2R, transponder 13, C-Band, 72 degrees
West Longitude, transponder frequency is 3960 MegaHertz, audio subcarrier is
6.8 MHz, polarization is vertical.
     Source:NASA Spacelink    Modem:205-895-0028  Internet:192.149.89.61
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=--=--=START=--=--= NASA Spacelink File Name:930217A.REL

2/17/93:  SPACEWALK  ADDED TO APRIL SPACE SHUTTLE FLIGHT

Ed Campion
Headquarters, Washington, D.C.                                  February 17, 199
3

James Hartsfield
Johnson Space Center, Houston

RELEASE:  93-31

     A spacewalk has been added to Space Shuttle mission STS-57 aboard
Endeavour, set for an April launch, as part of a series of spacewalk tests NASA
will conduct during the next three years to prepare for the construction and
maintenance of Space Station Freedom.

         The main objectives of the STS-57 mission are to retrieve the European
Retrievable Carrier (EURECA) deployed during a Shuttle flight in August 1992
and to conduct research in the Spacehab module which more than doubles the
amount of middeck research locker space aboard the orbiter.

     In addition to accomplishing the general objectives of the spacewalk test
series, the STS-57 extravehicular activity (EVA) will allow some of the
spacewalking procedures, using the Shuttle's mechanical arm, planned for use in
servicing the Hubble Space Telescope (HST), to be tested.  Those procedures
involve work by astronauts on a platform at the end of the Shuttle's arm.  The
arm will be aboard Endeavour for grappling the EURECA satellite.

     "The EVA will benefit us in two ways: first, we'll gather generic data on
human performance capabilities and limitations in space and secondly, we'll
perform some tasks similiar to those required for the HST mission later this
year," said Ron Farris, Chief of the Extravehicular Section at the Johnson
Space Center."

         "We'll also demonstrate that the EVA community can plan, train and fly
four missions this year and in that sense, it will be a banner year for EVA and
will be somewhat representative of the EVA efforts required to build and
maintain Space Station Freedom," Farris added.

     The spacewalk tests, as performed during STS-54 in January, concentrate on
defining the limits of spacewalking abilities, better understanding the
differences between true weightlessness and the ground training facilities that
simulate weightlessness and gaining more insight into the times required for
various tasks to be performed while spacewalking.  The tests also expand the
spacewalk experience levels among the astronaut corps, Shuttle flight
controllers and spacewalk training instructors.

     The specific tasks to be performed on STS-57 are still being evaluated by
flight planners, however they will concentrate on these goals and be similiar
to the STS-54 tasks although they will feature use of the robot arm.  The STS-
57 spacewalk, as with the STS-54 spacewalk and other such spacewalk tests will
be done without any impact on the mission's main objectives and will carry a
low priority among the mission's tasks.

     STS-57 crew members G. David Low and Jeff Wisoff will perform the EVAs.

     With the spacewalk performed in January, those planned for April and July
and the spacewalks planned for the STS-61 HST servicing mission in December, a
total of four Shuttle flights this year feature spacewalks.

        Four Shuttle missions with planned spacewalks in one year ties a NASA
record for missions with EVAs set when four spacewalk missions were flown in
1984.
     Source:NASA Spacelink    Modem:205-895-0028  Internet:192.149.89.61
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