MARSBUGS:  
The Electronic Exobiology Newsletter
Volume 4, Number 15, 17 November, 1997.

Editors:

David Thomas, Department of Biological Sciences, University of 
Idaho, Moscow, ID, 83844-3051, USA, thoma457@uidaho.edu or 
Marsbugs@aol.com.

Julian Hiscox, Division of Molecular Biology, IAH Compton 
Laboratory, Berkshire, RG20 7NN, UK.  Julian.Hiscox@bbsrc.ac.uk or 
Marsbug@msn.com

MARSBUGS is published on a weekly to quarterly basis as warranted 
by the number of articles and announcements.  Copyright of this 
compilation exists with the editors, except for specific articles, 
in which instance copyright exists with the author/authors.  E-
mail subscriptions are free, and may be obtained by contacting 
either of the editors.  Contributions are welcome, and should be 
submitted to either of the two editors.  Contributions should 
include a short biographical statement about the author(s) along 
with the author(s)' correspondence address.  Subscribers are 
advised to make appropriate inquiries before joining societies, 
ordering goods etc.  Back issues may be obtained via anonymous FTP 
at:  ftp.uidaho.edu/pub/mmbb/marsbugs.

The purpose of this newsletter is to provide a channel of 
information for scientists, educators and other persons interested 
in exobiology and related fields.  This newsletter is not intended 
to replace peer-reviewed journals, but to supplement them.  We, 
the editors, envision MARSBUGS as a medium in which people can 
informally present ideas for investigation, questions about 
exobiology, and announcements of upcoming events.

Exobiology is still a relatively young field, and new ideas may 
come out of the most unexpected places.  Subjects may include, but 
are not limited to:  exobiology proper (life on other planets), 
the search for extraterrestrial intelligence (SETI), ecopoeisis/ 
terraformation, Earth from space, planetary biology, primordial 
evolution, space physiology, biological life support systems, and 
human habitation of space and other planets.
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[I'm sorry for the delay in getting this out, but I am preparing 
to take my comprehensive exams for my Ph.D., and my time has been 
severely limited.  DJT]


INDEX

1)	MARS PATHFINDER ROVER EXITS ROCK GARDEN TO BEGIN LONG TREK

NASA release 97-217

2)	SCIENTISTS DEVELOP NEW MAP OF THE WORLD'S SEA FLOORS

NOAA release 97-56

3)	THE SOUTH POLE UNDER SCRUTINY BY RADARSAT

CSA release

4)	SPACE STATION SCIENCE OPPORTUNITIES
NASA release

5)	FIRST MARS GLOBAL SURVEYOR IMAGES AVAILABLE
by Ron Baalke

6)	MARS GLOBAL SURVEYOR UNVEILS ITS FIRST PORTRAIT OF MARS

JPL release

7)	FIRST IN-SPACE DIET ASSESSMENT, CREATED BY UC BERKELEY 
EPIDEMIOLOGIST, WILL BEAM DOWN FRIDAY FROM MIR SPACE STATION.

By Patricia McBroom

8)	PATHFINDER TEAM PAINTS AN EARTH-LIKE PICTURE OF EARLY MARS
JPL release

9)	SUCCESSFUL LAUNCH OF CASSINI-HUYGENS MISSION

ESA release 32-97

10)	JPL DIRECTOR EXPECTS LIFE TO BE FOUND ON OTHER PLANETS

LSU News Service

11)	NASA "SPACE SUITS" HELP BROTHERS WITH RARE GENETIC DEFECT

JSC release J97-30

12)	EXPLORING MARS FOR EVIDENCE OF PAST OR PRESENT LIFE

ARC release 97-75AR

13)	NASA JOINS CRUSADE FOR WOMEN'S HEALTH

NASA release 97-244

14)	MARS GLOBAL SURVEYOR TO RESUME AEROBRAKING

NASA release 97-249

15)	NASA ASTROBIOLOGY INSTITUTE PROPOSALS SOLICITED

16)	UB ARCHITECTURE STUDENTS DESIGN HOTELS IN SPACE, INCLUDING 
ONE BUILT INSIDE A 'CAPTURED' ASTEROID
SUNY Buffalo release 

17)	GALILEO:  COUNTDOWN TO EUROPA
by Ron Baalke 

18)	MARS PATHFINDER WINDS DOWN AFTER PHENOMENAL MISSION
JPL release

19)	SURVEYOR RESUMES AEROBRAKING, HEADING TOWARD NEW MAPPING 
ORBIT
NASA release 97-262

20)	CORNELL ROVER TO LAND ON MARS IN 2001:  $17 MILLION ATHENA 
PROJECT WILL EXPLORE MARTIAN HIGHLANDS
Cornell University release

21)	MARS PATHFINDER MISSION STATUS REPORTS

22)	MARS GLOBAL SURVEYOR MISSION STATUS REPORTS

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MARS PATHFINDER ROVER EXITS ROCK GARDEN TO BEGIN LONG TREK

NASA release 97-217



After 83 days of atmospheric, soil and rock studies, NASA's Mars 
Pathfinder is moving into extended mission activities that will 
take the rover on its longest trek yet, while the lander camera 
completes its biggest and best landscape panorama.

"The lander and rover performance continues to be nothing short of 
extraordinary," said Brian Muirhead, Mars Pathfinder project 
manager at NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA.  
"We have proven that we know how to design robust robots to 
operate in the hostile environment of Mars."

The rover has just completed its last alpha proton X-ray 
spectrometer study for a while, taking compositional measurements 
of a rock nicknamed Chimp, located just behind and to the left of 
an area scientists call the Rock Garden.  Once data from the 
spectrometer have been retrieved, Sojourner will begin a 164-foot 
(50-meter) clockwise stroll around the lander to perform a series 
of technology experiments and hazard avoidance exercises.

Meanwhile, the Pathfinder lander camera is continuing to image the 
Martian landscape in full-resolution color as part of its goal to 
provide a "super panorama" image of the Ares Vallis landing site.  
Each frame of this panorama is imaged using 12 color filters plus 
stereo.

"The super pan will be our biggest and best imaging data product," 
Muirhead said.  "It is made up of 1 gigabit (1 billion bits) of 
data, of which we've received more than 80 percent.  Given our 
limited downlink opportunities, we should have the full image by 
the end of October."

The 22-pound (10.5-kilogram) rover has survived 10 times longer 
than its primary mission design of seven days, while the lander 
has now been operating 2.5 times longer than it was originally 
expected to operate, according to Richard Cook, Mars Pathfinder 
mission manager.

Both vehicles are solar-powered, but carried batteries to conduct 
night-time science experiments and keep the lander warm during the 
sub-freezing nights on Mars.  Normal usage has fully depleted the 
rover's non-rechargeable batteries, limiting it to daylight 
activities only.  The lander battery, which packed more than 40 
amp-hours of energy on landing day, performed perfectly during the 
30-day primary mission, but is now down to less than 30 percent of 
its original capacity.

"We expected to begin seeing this type of degradation on both 
vehicles and, of course, designed both the lander and rover to 
operate without batteries altogether," Cook said.  "If everything 
else continues to operate properly, we could continue conducting 
surface experiments for months."

About once every two weeks, the lander battery is used to perform 
some nighttime science experiments, he added.  The primary 
activity is acquiring meteorological data and images of morning 
clouds, as well as images of Mars' two small moons, Phobos and 
Deimos.

Despite the lack of battery power, the rover has continued taking 
successful spectrometer readings during the day.  In the next two 
weeks, engineers will drive the vehicle back to a magnetic target 
on the ramp from which Sojourner first touched Martian soil.

"This analysis of the dust on the ramp magnet is a very important 
science measurement," noted Dr. Matthew Golombek, Mars Pathfinder 
project scientist.  "The results should give us a clue about how 
all this magnetic dust was formed."

Recent images and movies from Mars Pathfinder activities continue 
to be posted to the Internet at the following URL:
http://marsweb.jpl.nasa.gov

The Mars Pathfinder mission is managed by the JPL for NASA's 
Office of Space Science, Washington, DC.  The mission is the 
second in the Discovery Program of fast track, low-cost spacecraft 
with highly focused science goals.  JPL is a division of the 
California Institute of Technology, Pasadena, CA.
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SCIENTISTS DEVELOP NEW MAP OF THE WORLD'S SEA FLOORS

NOAA release 97-56


Scientists have used gravity data from satellites in addition to 
depth soundings from ships to produce a more defined, high 
resolution map of the world's ocean floors, the Commerce 
Department's National Oceanic and Atmospheric Administration 
announced today.

The new map, which looks similar to one the scientists published 
in 1995, provides estimations of the ocean depths from gravity 
data from satellites.  The 1995 map was based on gravity data, but 
did not provide estimations of ocean depths.

Scientists Walter H.F.  Smith of NOAA's National Oceanographic 
Data Center and David T.  Sandwell of the Scripps Institution of 
Oceanography, University of California, San Diego, report on their 
project in the September 26 issue of Science magazine.

Conventional sea floor mapping using echo sounding data from ships 
has been difficult because of the large gaps between surveys in 
remote areas.  "There are places as large as the State of Oklahoma 
where no soundings are available," said Smith.  "Traditionally, 
bathymetric contours are drawn by hand so that human intuition (or 
prejudice) fills the gaps in coverage," Smith and Sandwell write 
in Science.  "Recent developments allow a new approach to this 
problem."  Smith and Sandwell used gravity data from satellites to 
estimate depths in unsurveyed areas, thus filling the gaps in the 
map in an objective and high-resolution manner.

The new topography reveals all of the intermediate and large-scale 
structures of the ocean basins, including new mountain ranges such 
as the Foundation Seamounts in the South Pacific.  These were not 
found by conventional mapping but were revealed by the satellite 
gravity data.  Smith and Sandwell showed that uncharted seamounts 
are a significant source of topographic variation, and information 
from satellite gravity can reduce the error in estimated 
topographic variation by more than half.

Knowledge of sea floor topography is vital for understanding 
physical oceanography, marine biology, chemistry and geology.  
Topography influences currents, tides, and mixing and upwelling of 
nutrient-rich water.  The new topographic features portrayed by 
Smith and Sandwell reveal new fish habitats and should influence 
computer simulations of ocean circulation, which are used to 
forecast global climate change.

The map can be viewed on the World Wide Web at:
http://www.goes.noaa.gov/special.html

For more information and images on the World Wide Web, go to:
http://www.ngdc.noaa.gov/mgg/announcements/announce_predict.html
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THE SOUTH POLE UNDER SCRUTINY BY RADARSAT

CSA release


St.  Hubert, Sept.  29, 1997

The Canadian Space Agency (CSA)released today the first high-
resolution satellite image ever taken of the South Pole.  The 
image was acquired on 14 September by RADARSAT, Canada's first 
Earth observation satellite operated by the CSA.  The image, 
acquired at night, clearly shows the modern infrastructure of the 
Amundsen-Scott Station and also shows the runway and the remains 
of the old South Pole Station established in the late 1950's and 
now buried under about 10 meters of snow.  The Amundsen-Scott 
Station is operated by the U.S. National Science Foundation and 
supports a host of international science programs.  This image and 
several other images can be seen and retrieved from the CSA 
RADARSAT WEB site at the address given below.

This unique image of the South Pole was obtained by rotating the 
RADARSAT satellite 180 degrees in yaw.  This maneuver was 
performed for the Antarctic Mapping Mission (AMM), between 
September 9 and 11.  The maneuver allowed the radar to image to 
the left of the satellite track instead of to the right and by 
steering the radar beam up to cover the South Pole.  This coverage 
is not possible with other high-resolution sensors because of a 
combination of their orbit inclination and field of view 
capability.  Although other missions do regular yaw maneuvers for 
sun data acquisition purposes, the AMM maneuver is believed to be 
unique for an earth observation spacecraft like RADARSAT.  The 
satellite will remain in this configuration until November 3 to 
allow the complete mapping of Antarctica at high resolution.  This 
mapping of Antarctica, a largely uncharted region the size of 
Canada and Alaska combined will take 18 days to complete and will 
require the collection of over 5000 images.

The RADARSAT AMM has important significance for the scientific 
community; almost 70% of the Earth's fresh water is contained in 
the Antarctic region, and changes in this enormous reservoir 
directly influence world sea levels and climate.  A high-
resolution digital image mosaic of the ice sheet and exposed 
portions of the continent will be prepared from images taken by 
RADARSAT.  The new digital radar map will provide an unprecedented 
detailed portrayal of the surface form and features of the 
icesheet.  This RADARSAT based map will help scientists to better 
understand the dynamic behavior of the ice sheet and provide them 
a greater insight into the effects of human activity on the 
Southern Continent.

The RADARSAT AMM data will also serve as a benchmark for testing 
the predicted effects of global warming on the interior ice sheet 
and the bounding ice shelves, some of which have recently under 
gone rapid retreat especially in the Antarctic Peninsula.

Using the images taken by RADARSAT, scientists will be able to 
examine for the first time the effects of complex climatological, 
glaciological and geological processes on the Antarctic at high 
resolution and on a Continental wide scale.  Furthermore, the 
availability of this unique data set will be welcomed by 
scientists from many of the nations interested in the governance 
and protection of Antarctica in accordance with the Antarctic 
Treaty System.

The AMM is a commitment that was negotiated and agreed to by the 
CSA in an International Memorandum of Understanding (IMOU) signed 
with the National Aeronautics and Space Administration (NASA) and 
the National Oceanographic and Atmospheric Administration (NOAA) 
on February 27, 1991.  In exchange for the launch of the RADARSAT 
satellite by NASA, Canada agreed to provide the USA with access to 
a proportionate amount of RADARSAT's SAR on-time and to execute a 
yaw maneuver of the spacecraft twice during the mission to allow 
the mapping of the Antarctic Continental Ice Sheet.

Partners in the AMM include the CSA and NASA.  CSA support draws 
upon the Canada Center for Remote Sensing (CCRS) and RADARSAT 
International (RSI).  NASA support draws upon the Byrd Polar 
Research Center of the Ohio State University (OSU), NASA's Alaska 
SAR Facility (ASF), NASA's Jet Propulsion Laboratory (JPL) and the 
Goddard Space Flight Center (GSFC), Vexcel Corporation, the 
Environmental Research Institute of Michigan and the National 
Imagery and Mapping Agency.

Launched in November 1995 and operated by the CSA from Saint- 
Hubert, Quebec, RADARSAT uses a sophisticated microwave radar 
system to produce images of extraordinary clarity through cloud 
cover, smog, haze, smoke, and even in darkness.  The satellite can 
be programmed to capture images of an area as wide as 500 
kilometers, and can detect objects as small as eight meters.  
Marketing and worldwide distribution of RADARSAT data have been 
licensed to the Canadian firm, RADARSAT International (RSI), of 
Richmond, British Columbia.  With the AMM, RADARSAT will complete 
the detailed radar mapping of the entire planet Earth.

For further information:  Isabelle Hudon, CSA, (514) 926-4355, 
www.space.gc.ca, http://radarsat.space.gc.ca

NOTE:  The images are available at 
http://radarsat.space.gc.ca/ENG/AMM/images.html
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SPACE STATION SCIENCE OPPORTUNITIES
NASA release



Opportunities to conduct science experiments aboard the 
International Space Station will be limited during its assembly 
period, but the wait should be worth it, a top NASA scientist said 
Thursday.

"What we are about to build is a laboratory, a fully operational 
platform that is going to let us do things we never thought of 
before at scales we never considered before," said Dr. Ray Askew, 
space station senior scientist at NASA Headquarters.  He spoke 
recently at the AIAA Defense and Space Programs and Conference.

The full story at
http://science.msfc.nasa.gov/newhome/headlines/msad26sep97_1.htm 
------------------------------------------------------------------

FIRST MARS GLOBAL SURVEYOR IMAGES AVAILABLE
by Ron Baalke

The first images taken by the Mars Global Surveyor spacecraft 
while it has been in orbit around Mars are now available on

the Mars Global Surveyor home page (click on "First Images From 
Mars!"):


http://marsweb.jpl.nasa.gov/mgs/

Launched on November 7, 1996, Mars Global Surveyor entered Mars 
orbit on Thursday, September 11, 1997.  The spacecraft has been 
using atmospheric drag to reduce the size of its orbit for the 
past three weeks, and will achieve a circular orbit only 400 km 
(248 mi.) above the surface early next year.  Mapping operations 
begin in March 1998.  At that time, MOC narrow angle images will 
be 5-10 times higher resolution than these pictures.

Malin Space Science Systems and the California Institute of 
Technology built the MOC using spare hardware from the Mars 
Observer mission.  MSSS operates the camera from its facilities in 
San Diego, CA.  The Jet Propulsion Laboratory's Mars Surveyor 
Operations Project operates the Mars Global Surveyor spacecraft 
with its industrial partner, Lockheed Martin Astronautics, from 
facilities in Pasadena, CA and Denver, CO.

Contact:  info@msss.com
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MARS GLOBAL SURVEYOR UNVEILS ITS FIRST PORTRAIT OF MARS

JPL release


Mars Global Surveyor's first look at Mars is showing scientists a 
world devoid of an active core and anything more than the relic of 
an ancient magnetic field.



"Mars no longer has a global magnetic field generated by an 
internal energy source, like Earth and the other planets," said 
Dr. Jack Connerney, co-investigator of the magnetometer/electron 
spectrometer team, at an Oct.  2 Mars Global Surveyor press 
briefing at NASA's Jet Propulsion Laboratory.  "It appears that 
the crust of Mars is strewn with multiple magnetic anomalies, 
which may represent the solidification of magma as it was coming 
up through the crust and cooling very early in Mars' evolution, 
but this is only the memory of a magnetic field."

Mars Global Surveyor went into orbit around Mars on Sept.  11 
after a 10-month journey to the planet, and detected the presence 
of a weak magnetic field within a week of its arrival.  Evidence 
of this faint magnetic field confirmed long-standing theories that 
the red planet had, at one time in its history, a liquid core able 
to support a dynamo.  Scientists believe this core probably froze 
and solidified early in the planet's evolution.

The magnetometer data, acquired during one of the spacecraft's 
highly elliptical orbits around Mars during the week of Sept.  15-
18, indicates that the planet's magnetic field is not globally 
generated in the planet's core, but is localized in particular 
areas of the crust, said Dr. Daniel Winterhalter, magnetometer 
experiment representative at JPL.  Scientists plan to correlate 
these strong magnetic anomalies with topographical data obtained 
by Global Surveyor's camera and laser altimeter.  That information 
may lead to the identification of particular topographic features 
in the crust.

"The identification of these magnetic anomalies and their 
correlation with surface features may enable us to trace the 
history of the planet's interior, just as we are able to trace the 
history of Earth's interior using the magnetic anomalies that have 
been imprinted on the ocean floors," Winterhalter said.

Mars' very localized field also creates a new paradigm for the way 
in which it interacts with the solar wind, one that is not found 
with other planets.  While Earth, Jupiter and other planets have 
large magnetospheres, and planets like Venus have strong 
ionospheres, Mars' small, localized magnetic fields are likely to 
produce a much more complicated interaction process as these 
fields move with the planet's rotation.

These observations and many more came just as the spacecraft 
finished the walk-in phase of aerobraking and was about to begin 
the main phase, which will last three months.  All six of the 
spacecraft's science instruments had been turned on midway through 
the elliptical walk-in phase for calibration and engineering 
adjustments.  Since its capture, the spacecraft's orbit has been 
reduced from 45 hours to 40 hours, 20 minutes.  Through January 
1998, the aerobraking and navigation teams will gradually 
circularize Surveyor's orbit into the final two-hour, 378-
kilometer (234-mile) mapping orbit.

"The spacecraft and science instruments are operating 
magnificently," reported Dr. Arden Albee, of the California 
Institute of Technology, Pasadena, CA, who is the Mars Global 
Surveyor project scientist.  "The initial science data we've 
obtained from the walk-in phase of aerobraking are remarkable in 
their clarity, and the combined measurements from all of the 
instruments over the next two years are going to provide us with a 
fascinating new global view of the planet."

Mars Global Surveyor carries six science instruments--a camera, 
laser altimeter, magnetometer/electron reflectometer, thermal 
emission spectrometer and ultra-stable oscillator--that will paint 
a global portrait of Mars, gathering data on the planet's 
atmosphere, surface and interior.  The mission will enable 
scientists to determine Mars' current state and some of the major 
turning points in its evolution.  Among a myriad of science 
objectives, Global Surveyor will study Mars' climate and its 
resources, and attempt to determine if life ever existed on the 
planet.

During the past three weeks, the spacecraft has been aerobraking 
through the upper atmosphere of Mars each time it passes closest 
to the surface.  Aerobraking operations are continuing to proceed 
smoothly.  The spacecraft has completed 12 revolutions around 
Mars, including nine aerobraking passes through the upper Martian 
atmosphere, said Dr. Richard Zurek, an investigator at JPL who is 
leader of the Mars Global Surveyor atmospheric advisory team.  
Each of these atmospheric passes takes place at the start and low 
point of the orbit, known as the periapsis, as Global Surveyor 
orbits at current altitudes of about 110 kilometers (70 miles).

So far, the upper atmospheric density has varied according to 
daytime and nighttime measurements by as much as 70 percent, said 
Dr. Gerald Keating, on the atmospheric advisory team from George 
Washington University, Washington, DC.  And densities are five 
times higher than they were when the Mars Pathfinder spacecraft 
entered the upper atmosphere on July 4.  Density profiles are 
being acquired on a daily basis and used to help guide the 
aerobraking team's work to shrink and circularize the spacecraft's 
orbit.  Although the thickness of the Martian atmosphere continues 
to run slightly higher than predicted, no major changes to the 
aerobraking strategy are being considered because the spacecraft 
was designed to tolerate up to a 70 percent increase in 
atmospheric thickness.

The first orbital images of the Martian surface in more than 20 
years are showing geologic features that would dwarf some of the 
most spectacular features known to Earth.  Initial science data 
show a canyon far deeper than Arizona's 1-mile-deep Grand Canyon 
and mountains standing much taller than Nepal's Mt.  Everest.  
Vast expanses of smooth crustal flatlands in the northern 
hemisphere hint at a geologically younger portion of Mars, while 
new measurements of the planet's southern polar cap indicate 
drastically frigid temperatures of about minus 129 degrees Celsius 
(200 degrees Fahrenheit).

Mars Global Surveyor's camera revealed two regions of interest to 
geologists:  a view of a highland valley network called Nirgal 
Vallis and an image of Labyrinthus Noctis, an area west of the 
Valles Marineris near the crest of a large updoming in the Martian 
crust.  Dr. Michael Malin, of Malin Space Science Systems Inc., 
San Diego, who is the principal investigator of the Mars Global 
Surveyor camera, presented the images.

Nirgal Vallis is about 15 kilometers (9 miles) across by about 45 
kilometers (27 miles) in length, with many small sand dunes and 
different aged craters in the vicinity, Malin said.  The valley is 
located at 28.5 degrees south latitude, 41.6 degrees west 
longitude.  Of interest to scientists are the processes that 
helped shape this canyon.

"The origin of this and many other canyons on Mars has been 
debated ever since the Mariner 9 mission," Malin said.  "There are 
two leading theories:  the first suggests that water flowing over 
the surface accumulated, as it does on Earth, then formed a 
drainage basin that allowed the water to flow further down into a 
larger channel.  The alternative explanation was that ground water 
processes dissolved part of the subterranean materials on Mars, 
causing collapse and progressive deterioration of this particular 
region."

Labyrinthus Noctis, the second image presented Oct.  2, is near 
the crest of a large updoming of the Martian crust that is 
probably thousand of kilometers in diameter, and near very large, 
2,000-meter-deep (6,500-foot) canyons bounded by faults.  Debris 
shed from the steep slopes has moved down into the region after 
the canyons opened.  Small dunes are seen in the lower portion of 
this area, beneath the high cliffs.

Global Surveyor's camera has acquired about a dozen high 
resolution images of Mars to date, which are being used to fine- 
tune the instrument in preparation for the start of mapping 
operations in March 1998.  These first images were not the highest 
resolution expected during mapping because the spacecraft is not 
yet in the proper mapping orbit and the correct sunlight 
conditions have not yet been reached, Malin said.  As the 
spacecraft moves into its Sun-synchronous orbit, in which it will 
cross the Martian equator at 2 p.m.  local Mars time during each 
revolution, the Sun will be at a standard angle above the horizon 
in each image.

The spacecraft's thermal emission spectrometer recorded sub- 
freezing temperatures at the southern polar cap, said principal 
investigator Dr. Philip Christensen of Arizona State University, 
Tempe.  The instrument, which takes infrared measurements on the 
surface, also recorded temperature highs of about -7 C (20 F) at 
the warmest parts of the planet and a very clear, dust-free 
atmosphere.

The laser altimeter, which fires 10 laser pulses a second at the 
surface, is also performing well, reported Dr. David Smith, 
principal investigator of the instrument and based at the NASA 
Goddard Space Flight Center, Greenbelt, MD.  This experiment will 
measure the height of Martian surface features and provide 
elevation maps that will be precise to within 30 meters (98 feet) 
of surface features.  From the 12,000 measurements already taken, 
Smith reported a notable inaccuracy in the location of some 
Martian features as shown on current maps based on Viking data.  
Global Surveyor will provide a much more accurate global map, 
which will be used to guide future missions to the surface.

Additional information about the Mars Global Surveyor mission is 
available on the World Wide Web by accessing JPL's Mars news site 
at http://www.jpl.nasa.gov/marsnews or the Global Surveyor project 
home page at http://mars.jpl.nasa.gov.

Mars Global Surveyor is the first in a sustained program of Mars 
exploration, known as the Mars Surveyor Program.  The Jet 
Propulsion Laboratory manages the mission for NASA's Office of 
Space Science, Washington, DC.  JPL's industrial partner is 
Lockheed Martin Astronautics, Denver, CO, which developed and 
operates the spacecraft.  JPL is a division of the California 
Institute of Technology, Pasadena, CA.
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FIRST IN-SPACE DIET ASSESSMENT, CREATED BY UC BERKELEY 
EPIDEMIOLOGIST, WILL BEAM DOWN FRIDAY FROM MIR SPACE STATION.
UC Berkely release
By Patricia McBroom

On Friday (October 10), U.S.  astronaut David Wolf, who recently 
began a four-month stay on the Russian Mir space station, will 
beam down the first in-flight record of a diet eaten in space.

Created by public health epidemiologist Gladys Block of the 
University of California at Berkeley, the record is a weekly 
intake questionnaire designed specifically to counter the effects 
of extended weightlessness.

For the first time, food and liquid intake can be systematically 
measured and modified while the astronaut is in space, said Block, 
whose dietary assessments are widely used by nutritional 
scientists.  The space diet evaluation includes a formula for 
translating Wolf's weekly food log into measures of calcium, 
sodium, iron, fluid, calories and protein.

"We've never been able to do this in real time before," said 
Block, a professor in UC Berkeley's School of Public Health.  "If 
we discover that Wolf's fluid intake is low, the flight surgeon 
can say, 'You've got to drink more water.' "

Block said scientists hope to have an impact on such possible 
consequences of extended space flight as kidney stones and bone 
loss.

Long-duration space flight has serious effects on the human body, 
including loss of weight, bone and muscle; changes in blood cells, 
and increased risk of kidney stone formation, according to Scott 
M.  Smith, nutritional scientist with NASA's Johnson Space Center 
in Houston, who will receive the results of Wolf's weekly 
questionnaire.

Smith said these physiological hazards, particularly the risk of 
bone loss, will increase significantly with the extended space 
flight envisioned for the International Space Station, due for 
inauguration in 1998.

"In my opinion, bone loss is one of the most critical things we 
must fix before we can do anything like send humans to Mars," said 
Smith.

Experience with three decades of space flight has shown that 
individuals vary greatly on bone loss, said Smith.  Some 
astronauts have recovered completely, while others have not yet 
returned to pre-flight levels.

The total diet available on Mir comprises approximately 250 food 
items, about half of which are Russian foods.  Daily menus are 
created for astronauts, but they often swap foods or otherwise 
change the diet while in flight, said Smith.

The questionnaire of 50-60 items took several months to develop, 
but it takes only ten minutes to answer, Block said.

Pre-flight ground tests with NASA volunteers demonstrated the 
ability of such a brief questionnaire to estimate fluid and 
nutrient intake thought to be critical for health during space 
flight.  The volunteers ate a space station diet while living in a 
capsule for 60 days.
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PATHFINDER TEAM PAINTS AN EARTH-LIKE PICTURE OF EARLY MARS

JPL release


Mars is appearing more and more like a planet that was very Earth-
like in its infancy, with weathering processes and flowing water 
that created a variety of rock types and a warmer atmosphere that 
generated clouds, winds and seasonal cycles.

Those observations, along with new images taken by the Mars 
Pathfinder rover and lander, and an update on the condition of the 
spacecraft, were presented at an Oct.  8 press briefing 
originating from NASA's Jet Propulsion Laboratory.

"What the data are telling us is that the planet appears to have 
water-worn rock conglomerates, sand and surface features that were 
created by liquid water," said Dr. Matthew Golombek, Mars 
Pathfinder project scientist at JPL.  "If, with more study, these 
rocks turn out to be made of composite materials, that would have 
required liquid water flowing on the surface to round the edges in 
pebbles we see on the surface or explain how they were embedded in 
larger rocks.  That would be a very important finding."

Golombek also stressed the amount of differentiation--or heating, 
cooling and recycling of crustal materials--that appears to have 
taken place on Mars.  "We're seeing a much greater degree of 
differentiation--the process by which heavier elements sink to the 
center of the planet while lighter elements rise to the surface--
than we previously thought, and very clear evidence that liquid 
water was stable at one time in Mars' past.

"Water, of course, is the very ingredient that is necessary to 
support life," he added, "and that leads to the $64,000 question:  
Are we alone in the universe?  Did life ever develop on Mars?  If 
so, what happened to it and, if not, why not?"

Despite recent communications problems with Earth, the Mars 
Pathfinder lander and rover are continuing to operate during the 
Martian days, when they can receive enough energy to power up 
spacecraft systems via their solar panels.  The mission is now 
into Sol 94, or the 94th Martian day of operations, since landing 
on July 4.

"Everything that we have seen over the last 10 days (with respect 
to communications) is like a twisty little maze with passages all 
alike," said Jennifer Harris, acting mission manager.  "I am happy 
to report that we have made contact with the spacecraft using its 
main transmitter.  We were able to confirm that we could send a 
command to the spacecraft to turn its transmitter on and then turn 
it off.

"We don't know yet whether we are receiving that signal over the 
low-gain or high-gain antenna," she added, "but we should be able 
to determine this over the next few days."

The Mars Pathfinder team began having communications problems with 
the spacecraft on Saturday, Sept.  27.  After three days of 
attempting to reestablish contact, they were able to lock on to a 
beacon signal from the spacecraft's auxiliary transmitter on 
October 1, which meant that the spacecraft was still operational.

At that time they surmised that the communications problems were 
most likely related to depletion of the spacecraft's battery and 
uncertainties in the onboard clock.  The last successful data 
transmission cycle from Pathfinder was completed at 3:23 a.m.  
Pacific Daylight Time on Sept.  27, which was Sol 83 of the 
mission.

Since then, efforts have been made during each Martian day to 
reestablish contact with both the primary and auxiliary 
transmitter and obtain engineering telemetry that would tell the 
team more about the health of the lander and rover.  On Oct.  7, 
the team was able to lock on to Pathfinder's signal, via NASA's 
Deep Space Network 34-meter-diameter (112-foot) dish antenna in 
Madrid, Spain, for about 15 minutes, using the main transmitter.  
However, in repeating the process on Oct.  8, they did not receive 
a signal.

The rover, which receives its instructions from Earth via the 
lander, is currently running a contingency software program that 
was preprogrammed to start up if the vehicle did not hear from the 
lander after five Martian days.  That program was powered on Oct.  
6, on Sol 92 of the mission.  In this contingency mode, the rover 
is instructed to return to the lander and begin circling it.  This 
precaution is designed to keep Sojourner close to the lander in 
the event that the spacecraft was able to begin communicating with 
it again.

If normal communications are reestablished, the rover team will 
send new commands to Sojourner to halt the contingency circling 
and begin a traverse to a specific location.

Dr. William Folkner, an interdisciplinary scientist at JPL, 
presented data on the rotation and orbital dynamics of Mars, which 
are being obtained from two-way ranging and Doppler tracking of 
the lander as Mars rotates.  Measurements of the rate of change in 
Mars' spin axis have important implications for learning more 
about the density and mass of the planet's interior.  Eventually, 
scientists may be able to determine whether Mars' core is 
presently molten or fluid.  The size of the core also can be used 
to characterize the thickness, or radius, of Mars' mantle.

"By measuring the spin axis of Mars, we can learn something about 
the interior of the planet, because the speed of the change in its 
orientation is related to how the mass is distributed inside," 
Folkner said.  "If the core is fluid, its spin and the way in 
which the planet wobbles slightly will be different from the spin 
and wobble of a planet with a solid core.

"If Mars' core is solid, then it can't be less than about 1,300 
kilometers (807 miles) in radius, out of the planet's total radius 
of 3,400 kilometers (2,112 miles)," Folkner added.  "If the core 
is made up of something less dense than iron, if it's a mixture 
of, say, iron and sulfur, then the core would be bigger, but it 
couldn't be bigger than about 2,000 kilometers (1,242 miles) in 
radius."

New close-up images of dunes around the landing site are showing 
some scientists clear evidence that there is sand on the surface 
of Mars.  Identification of sand, as opposed to dust or pebbles, 
is a significant factor in establishing that weathering processes 
such as erosion, winds and flowing water all contributed to Mars' 
present landscape.

"We've made significant progress in establishing that water was a 
dominant agent in forming the surface, and now we can say that 
there is another agent at work, and that is the wind, that has 
created and modified some of the landforms on a smaller and medium 
scale," said Dr. Wes Ward of the U.S. Geological Survey, 
Flagstaff, AZ, a member of the Imager for Mars Pathfinder team.  
"And because the water is no longer there, wind probably is the 
dominant agent shaping the Martian surface at this moment."

Ward showed images of Ares Vallis, taken by the rover and Viking 1 
orbiter images to point out the structural difference in these 
surface features.  While Viking 1 surface features around a rock 
nicknamed "Big Joe" showed drifts, the dune-like surfaces in the 
Ares Vallis flood basin resemble sand that has been blown 
southwest over the landing site.  The presence of sand also points 
to the likely presence of liquid water, needed to create these 
small, 1-millimeter-diameter granules, and weathering agents such 
as wind to blow them into small ridges and moats present around 
the Ares Vallis rocks.

"The wind is quite an active agent," Ward said.  "Sand is the 
smoking gun, and as far as I'm concerned, the gun is smoking and 
has Colonel Mustard's prints all over it.  We are seeing sand at 
the landing site."

Dr. Greg Wilson, of Arizona State University, who is on the 
Pathfinder atmospheric experiment team, reported increases in the 
pressure of the Martian atmosphere and a drop in surface 
temperatures.

"We expect to see a continued increase in pressure and decrease in 
temperatures as the dust season approaches and winds begin to lift 
more dust into the Martian atmosphere," he said.  "The dust season 
on Mars usually begins in the next few weeks."

Additional information, images and rover movies from the Mars 
Pathfinder mission are available on JPL's Mars news media web site 
at http://www.jpl.nasa.gov/marsnews or on the Mars Pathfinder 
project's home page at http://marsweb.jpl.nasa.gov .  Images from 
Mars Pathfinder and other planetary missions are available at 
NASA's Planetary Photojournal web site at 
http://photojournal.jpl.nasa.gov.

The Jet Propulsion Laboratory manages the Mars Pathfinder mission 
for NASA's Office of Space Science, Washington, DC.  The mission 
is the second in the Discovery Program of fast-track, low-cost 
spacecraft with highly focused science goals.  JPL is a division 
of the California Institute of Technology, Pasadena, CA.
------------------------------------------------------------------

SUCCESSFUL LAUNCH OF CASSINI-HUYGENS MISSION

ESA release 32-97


ESA's latest and farthest venture into the Solar System began at 
10:43 Paris time on 15 October.  The American Titan IVB/Centaur 
launcher sent NASA's large Cassini spacecraft on its way to 
Saturn.  Cassini carries ESA's probe Huygens, as well as the high-
gain antenna provided by ASI, the Italian Space Agency.  In 2004 
ESA's Huygens probe will plunge into the thick atmosphere of 
Saturn's largest moon, Titan.

About 500 representatives of the scientific, engineering and 
industrial teams in Europe, which created the Huygens Probe, were 
present at Cape Canaveral for the Cassini Huygens launch.  They 
saw the powerful boosters of the Titan launcher light up the pre-
dawn sky.

The launch sequence concluded with the completion of the second 
firing and separation of the Centaur upper stage rocket.  NASA's 
ground station at Canberra, Australia, obtained good signals from 
Cassini an hour after launch.

The European Space Operations Center (ESOC) at Darmstadt will 
monitor the condition of the Huygens spacecraft.  Their report is 
expected in 8-10 days' time.

The next major event will be the swingby of Cassini Huygens at 
Venus on 21 April 1998.  This is the first of a sequence of 
"gravity-assist" operations at Venus, the Earth and Jupiter, to 
accelerate the spacecraft.
------------------------------------------------------------------


JPL DIRECTOR EXPECTS LIFE TO BE FOUND ON OTHER PLANETS

LSU News Service


26 September, 1997


BATON ROUGE -- Edward Stone, director of the Jet Propulsion 
Laboratory and vice president of the California Institute of 
Technology, said in a talk at LSU that he expects life will be 
found any place in the galaxy where there is liquid water.

Stone, who spoke Thursday night at the Lod Cook Alumni Center as 
the Max Goodrich Distinguished Speaker, chronicled NASA's search 
for life on other planets, beginning with the 1976 landings of the 
Viking spacecraft on Mars.  Although those experiments turned up 
nothing, the discovery on earth of tube worms living in the near-
boiling waters of deep ocean vents, and algae living beneath the 
ice sheets at the polar caps proved that life is much more robust 
than originally thought, he said.

Indications of life from a Martian meteorite found at the South 
Pole also gave impetus to the search for life elsewhere.

Stone said it is unlikely that life will be found on the surface 
of Mars because the sun's ultra-violet rays tend to sterilize the 
surface, but if there is liquid water underground, some form of 
life will probably be there.  Part of the mission of the Mars 
surveyor, which arrived at Mars last week, will be to look for 
"hot spots," where there may be liquid water.  It will be these 
hot spots where further exploration for life will take place, he 
said.

NASA has plans to send spacecraft to Jupiter's moon, Europa, and 
to Saturn's moon, Titan, to look for liquid water.  Both 
spacecraft should arrive in 2004.

The surface of Europa is thought to be ice, with the possibility 
of liquid water beneath.  Eventually a spacecraft may be sent to 
drill through the ice to gather information about Europa's 
climatological history and to probe the liquid water beneath.

Titan, as large as the planet Mercury, has a methane atmosphere, 
Stone said, but such an atmosphere is excellent for the formation 
of large, complex organic molecules--the type which gave rise to 
life on earth.  The Cassini spacecraft, which is now in Florida, 
will explore the chemistry of Titan's atmosphere and map its 
surface.

Another promising area in the search for life is on the surface of 
a comet.  Comets are covered with a black, sooty residue which may 
be organic, he said.  What this residue is, where it came from and 
whether it might possibly have seeded life on earth are all 
questions that need to be explored.  Plans are under way to 
capture some of this residue during a comet fly-by in 2004 and 
return it to earth.

Although Jupiter has atmospheric zones that are temperate and 
should contain liquid water, Stone said he did not expect life to 
be found there because the gasses in the atmosphere are constantly 
rising and falling out of these zones.  There are no stable places 
for life to get a foothold, he said.

And because NASA has made the search for life a high priority, 
exploration of Venus must wait until later.  Venus has a surface 
temperature of 900 degrees and little or no water, so it is an 
unlikely place to search for life.

Other projects include connecting the two Keck telescopes in 
Hawaii in such a way that they will act as part of a mirror with a 
diameter of the distance between them, and plans for an orbiting 
telescope based on the same principles.  This might permit us to 
see earth-sized planets around other stars.  An earth-sized planet 
is one-billionth as bright as its star, Stone said.

Ultimately, humans will be sent on a three-year, round trip to 
Mars.  NASA is addressing the challenges in feeding them, 
protecting them and getting them back now.
------------------------------------------------------------------


NASA "SPACE SUITS" HELP BROTHERS WITH RARE GENETIC DEFECT

JSC release J97-30
by Ann Hutchison


10 October, 1997


Technology being designed to protect astronauts working in space 
is helping two British youngsters enjoy a more normal life.

A team at NASA's Johnson Space Center, Houston, TX, recently 
provided two specially designed "space suits" to 4-year-old Kyle 
and 2-year-old Ryan Richards of Shotton Colliery, England.  The 
brothers suffer from Polymorphic Light Reaction Syndrome, which is 
caused by a very rare genetic defect.  It is characterized by 
extreme allergy to light that causes the skin to break out in 
rashes and blisters.  Without the suits, the boys could venture 
outside only at night.  Even exposure to a bright light bulb may 
cause an allergic reaction.

"An English newspaper journalist approached us earlier this year 
on behalf of the Richards family," said Robert Dotts, Assistant 
Director of Technology Transfer and Commercialization at JSC.  
After discussions with the family, NASA formed a small team and 
"set about defining suit requirements, identifying possible 
materials and testing them."  Based on test results, NASA 
engineers decided on a two-layer suit, plus an active cooling 
system to keep the children comfortable inside the suits.

The suit's outer layer consists of a white jacket, pants, gloves 
and head gear, including goggles.  The external garments protect 
the children's sensitive skin from more than 99.9 percent of the 
sun's ultraviolet (UV) rays.  The garments are made of a new 
material that should be available in several months from the Solar 
Protective Factory, Carmichael, CA.  The cooling undergarments, 
made of nylon/lycra, are based on a design worn by astronauts 
during spacewalks and sized for the children.  The cooling 
system--shorts and T-shirt fitted with tubes filled with ice-
cooled water--is operated by a battery-powered unit worn on the 
waist.

The JSC team (Dotts, NASA engineers Dominic Del Rosso and Evelyne 
Orndoff and Dr. Smith Johnston, a NASA physician) delivered the 
suits to the Richards family, which was on a trip to Orlando, FL, 
in late September.  They accompanied the youngsters on their visit 
to Disney World to assist with their first extended outing while 
wearing the UV protective suits.  While in Florida, the children 
also were able to watch a Space Shuttle launch.  According to 
Johnston, the NASA team closely monitored the children in the 
suits.  Testing involved first normal children, then the Richards 
boys inside the home in Florida, followed by a short excursion 
outside.  After a few minor modifications to the suits, the group 
made a six-hour excursion to Disney World.  "This was the first 
time Ryan had ever been outside in the daytime," Johnston said.

The suits worn by the Richards children are prototypes of space 
suits being developed at JSC.  "This should be a great way to test 
the durability of these suits," Dotts said.  "Who better to give 
them a real work-out than a couple of active, energetic 
youngsters?"

Dotts said the suits' performance was "fantastic for the first 
prototypes."  He said the team has identified "a few minor changes 
to the suits to improve their usability."  They plan to 
incorporate them into another prototype suit in the next month.

NASA provided the suits through an agreement with the HED 
Foundation, Hampton, VA, which since 1987 has provided cooling 
gear to children with hypohidrotic ectodermal dysplasia (HED) and 
with multiple sclerosis.  HED is a medical disorder characterized 
by a lack of sweat glands, which can lead to heat exhaustion, 
heatstroke and even death.

JSC also is working with MicroClimate, Inc., Sanford, MI, which 
has developed cooling garments using a phase-change material to 
provide the cooling.

Dotts said he hopes to develop a long-term agreement with the HED 
Foundation by the end of the year for distribution of similar UV 
suits to needy children in the U.S. and worldwide.  It is 
estimated that several thousand children around the world suffer 
from various defects that cause either extreme sensitivity to 
light or problems in cooling their bodies.

A photograph to accompany this release is available at the NASA 
Commercial Technology Network Web site at URL
http://www.nctn.hq.nasa.gov/success/index.html
------------------------------------------------------------------


EXPLORING MARS FOR EVIDENCE OF PAST OR PRESENT LIFE

ARC release 97-75AR
by Elizabeth Carter


17 October, 1997


Alternative exploration strategies designed to detect evidence of 
past or present life on Mars are the subject of a presentation to 
be given by NASA's Dr. Jack Farmer at the Geological Society of 
America (GSA) Annual Meeting in Salt Lake City, Utah, on Oct.  20, 
1997.

Farmer, an exobiologist and paleontologist at NASA's Ames Research 
Center, Moffett Field, CA, asks the question, "If there was life 
on Mars, where would it be found?" The crucial first step in 
implementing an exploration strategy is identifying the best 
places to look, he states.

"A close synergy between orbital and landed science will be 
essential for effective site selection to explore for past life," 
Farmer said.

In exploring for a Martian fossil record, present scenarios assume 
that rover missions in 2001 and 2003 will gather and cache samples 
for possible return-to-Earth mission in 2005.  A critical step is 
to locate accessible surface outcrops of water-formed sedimentary 
deposits on Mars.  The effectiveness of a sample return mission in 
addressing the question of past Martian life will be significantly 
enhanced by

1) obtaining high spatial resolution data from important sites 
during the 2001 orbital mission,

2) delivering highly mobile robotic platforms to 
exopaleontological sites in 2001 and 2003, e.g.  rovers that are 
capable of multiple kilometer traverses during nominal mission 
times, and

3) carrying out in-situ mineralogical and geochemical analyses of 
a variety of rock types as a basis for selecting samples for 
return to Earth.

Potentially important targets include fine-grained, clay-rich 
detrital sediments, water-lain volcanic ash deposits, and chemical 
precipitates--lithologies that on Earth have been shown to be 
especially favorable for preserving fossil biosignatures of 
microbial life.

According to Farmer, exploring for Martian life will require a 
fundamentally different approach than exploring for a fossil 
record.  A deep subsurface hydrosphere, touted as the most likely 
haven for an extant biota on Mars may yet exist beneath the 
Martian cryosphere at a depth of several kilometers.  However, 
during the Mars Global Surveyor (MGS) Program, robotic platforms 
will be unable to penetrate deeper than a few meters.

Farmer believes that the technological challenge of deep 
subsurface drilling presently provides the most compelling 
scientific reason for mounting human missions to Mars.  But as a 
first step in planning drilling missions, systematic orbital 
searches using high spatial resolution multispectral imaging 
should be undertaken sometime during the MGS Program (perhaps in 
2003) to identify spatially-restricted thermal anomalies, and 
concentrations of water, methane or other reduced gases that may 
indicate the presence of near surface hydrothermal systems.
------------------------------------------------------------------


NASA JOINS CRUSADE FOR WOMEN'S HEALTH

NASA release 97-244



NASA Administrator Daniel S. Goldin today unveiled dramatic new 
technological developments affecting women's health at two events 
on Capitol Hill.  The technologies, which grew out of spin-offs 
from the U.S.  space and aeronautics program, will usher in a new 
era in detection and treatment of women's health problems ranging 
from breast cancer to osteoporosis to reproductive health.

"As a husband, father of two daughters, and a grandfather, few 
subjects are as important to me as women's health," Goldin said.  
"That is why I am so proud of how NASA technologies, originally 
developed for our space and aeronautics programs, improve health 
care for women, men and children around the world."

In the first event, NASA signed an agreement enlisting NASA 
technologies to fight breast cancer and other women's illnesses.  
The agreement was signed by Dr. Henry McDonald, Director of NASA's 
Ames Research Center, Moffett Field, CA, and Dr. Susan Blumenthal, 
Assistant Surgeon General and Deputy Assistant Secretary for 
Women's Health at the Department of Health and Human Services 
(HHS).  At the signing ceremony, Goldin and McDonald demonstrated 
for Blumenthal six advanced technologies resulting from the U.S.  
space and aeronautics program that can dramatically influence the 
state of women's health.

The agreement between NASA and HHS establishes a cooperative 
framework between Ames and the Office on Women's Health to 
identify, develop and transfer NASA technologies to benefit 
women's health.  Major areas of concern are cancer, reproductive 
health, pregnancy, osteoporosis and education.

The technologies demonstrated included the new robotic "Smart 
Surgical Probe"; technology to allow three-dimensional "planning" 
for breast reconstruction, as is currently done for facial 
reconstruction surgery; and a device to predict an individual's 
specific risk of contracting osteoporosis.

At the second event, Goldin was the keynote speaker at a luncheon 
sponsored by the Congressional Caucus on Women's Issues discussing 
"Space Technology Contributions to Breast Cancer Research."  He 
highlighted several NASA research and technology programs that 
help scientists and doctors understand, diagnose and treat breast 
cancer.

"Part of the breast cancer story is that it kills thousands every 
year," Goldin said.  "However, this tragic statistic does not tell 
the whole story.  The rest of the story is one of hope.  It's a 
story of strength and grace and awesome courage.  At NASA, we are 
proud to be part of this story.  Before today, Americans may not 
have connected NASA with the fight against breast cancer.  They 
may not know that NASA is on the front line for women's health.  
We are pushing the edge of the envelope, developing state-of-the-
art technologies that will help save women's lives."

NASA Astronaut Mary Ellen Weber, Ph.D., explained how NASA efforts 
to grow human cells and tissue in space help researchers 
understand cancer and the response of the human immune system.  
Dr. Carolyn Krebs of NASA's Goddard Space Flight Center, 
Greenbelt, MD, provided information on the way technology allowing 
the Hubble Space Telescope to map distant stars is being used in 
doctors' offices today to easily detect tiny spots in breast 
tissue, using a needle for biopsy rather than surgery.

More information on the NASA technologies described above can be 
obtained from the NASA home page at URL:
http://www.nasa.gov/today/index.html
------------------------------------------------------------------

MARS GLOBAL SURVEYOR TO RESUME AEROBRAKING

NASA release 97-249


[For more on this, see the MGS flight reports at the end of this 
issue.  DJT]


After a two-week hiatus, NASA's Mars Global Surveyor (MGS) flight 
team will resume lowering the spacecraft's orbit around Mars 
beginning Nov.  7.  The effort will proceed at a more gradual pace 
than before, which will extend the mission's aerobraking phase by 
several months, and will change Global Surveyor's final science 
mapping orbit.

The decision to resume aerobraking came after intensive 
engineering analysis, computer simulations and tests with 
representative hardware to characterize the current condition of 
one of the spacecraft's two solar panels, which began to flex more 
than expected during the spacecraft's lowest dip into the Martian 
atmosphere on Oct.  6.

Under normal circumstances, the spacecraft's two 11-foot- long 
(3.5-meter) solar panels should remain fixed and nearly motionless 
during each aerobraking pass through the upper atmosphere of Mars.  
One of the panels, which did not fully deploy and latch after 
launch, moved past its latched position and has shown slight 
movement during the spacecraft's last three closest approaches to 
the Martian surface.

"After sufficient time to study the observed motion, we concluded 
that it is possible to perform additional aerobraking at a slower 
rate, without putting undue stress on the solar panel in 
question," said Glenn E.  Cunningham, Mars Global Surveyor mission 
manager at NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA.  
"This changes Mars Global Surveyor's final mapping orbit, but it 
should not have a significant impact on the ability of Global 
Surveyor to accomplish the mission science objectives."

The spacecraft's scientific instruments have performed flawlessly 
and continue to return new information about Martian magnetic 
properties, its atmosphere, surface features, temperatures and 
mineralogy since Mars Global Surveyor entered orbit around the red 
planet on Sept.  11.

The spacecraft is currently in a 35-hour elliptical orbit which 
brings it 107 miles (172 kilometers) above the surface of Mars at 
its closest approach to the planet.  The operations team at JPL 
and Lockheed Martin Astronautics, Denver, CO, will begin to reduce 
that orbit using a more moderate level of aerobraking that will 
slowly bring the spacecraft into the desired nearly circular 
mapping orbit.  Aerobraking, a technique first demonstrated in the 
summer of 1993 during the final months of the Magellan mission to 
Venus, allows a spacecraft to lower its orbit without relying on 
propellant, by using the drag produced by a planet's atmosphere.

"There are several types of desirable orbits for us to consider in 
the next several weeks that will give us global coverage of the 
planet and yield all of the science data we expected to return," 
Cunningham said.  "In the meantime, the instruments are performing 
marvelously, and we will continue gathering new science data as we 
begin to reduce the spacecraft's altitude and bring it down into 
the upper Martian atmosphere.  Even if we wind up in an elliptical 
orbit, we will have an opportunity to study Mars at closer range 
than we originally planned because the spacecraft's periapsis -- 
or closest passage over Mars -- will be closer than the 234-mile 
(378-kilometer) circular orbit that was to be its original mapping 
distance."

The spacecraft's current orbit was raised Oct.  12 after the 
flight operations team observed that the unlatched solar panel had 
moved more than 20 degrees and beyond what should have been its 
fully deployed and latched position.  Significant movement was 
observed on periapsis 15 -- or the 15th closest pass over Mars, 
which occurred on Oct.  6 -- when the Martian atmosphere had 
become twice as dense as it had been during previous passes.  The 
thickness of the atmosphere amounted to a 50 percent increase in 
pressure over what was expected on the spacecraft's solar array.

Although atmospheric variations like these were anticipated as the 
seasons change on Mars, the spacecraft's orbit was raised by about 
seven miles (11 kilometers) to adjust the pressure level.  
Subsequent motion of the panel at periapsis 16 through 18 caused 
the flight team to raise the orbit further on Oct.  12, taking the 
spacecraft out of the atmosphere altogether.

"The investigation of the unexpected motion of the unlatched panel 
led us to identify a secondary source of damage in the yoke, a 
piece of structure that connects the solar panel to the 
spacecraft," Cunningham said.  "This secondary source of damage 
was a result of the failure of the damper arm that jammed in the 
panel's hinge joint shortly after launch, when the solar panels 
were initially deployed."

Mechanical stress analysis tests suggest that the yoke -- a 
triangular, aluminum honeycomb material sandwiched between two 
sheets of graphite epoxy -- probably fractured on one surface.  
The analysis further suggests that the fractured surface, with 
increased pressure on the panel during aerobraking, began to pull 
away from the aluminum honeycomb beneath it.

"Aerobraking will be reinitiated at 0.2 newtons per square meter 
(0.00003 pounds per square inch), which is about one- third of the 
original aerobraking level," Cunningham said.  "This is a pressure 
that we currently believe is safe but we will continue to work 
with ground tests, analysis and close monitoring of in-flight 
spacecraft data to assure that it is safe."

"Aerobraking will take much longer, perhaps eight to 12 months, at 
this more gradual rate.  In the meantime, we will continue 
collecting science data and work in the next several weeks toward 
selection of the best possible orbit to fulfill the science 
objectives of the mapping mission," Cunningham said.

A new color image from the MGS Mars Orbiter Camera of the giant 
volcano Olympus Mons is available on the Internet at the following 
URL:
http://barsoom.msss.com/mars/global_surveyor/camera/images/index.h
tml

Additional information about the Mars Global Surveyor
mission is available on the World Wide Web by accessing JPL's Mars 
news site at URL:
http://www.jpl.nasa.gov/marsnews
or the Global Surveyor project home page at URL:
http://mars.jpl.nasa.gov.

Mars Global Surveyor is part of a sustained program of Mars 
exploration, known as the Mars Surveyor Program.  The Jet 
Propulsion Laboratory manages the mission for NASA's Office of 
Space Science, Washington, DC.  JPL's industrial partner is 
Lockheed Martin Astronautics, Denver, CO, which developed and 
operates the spacecraft.  JPL is a division of the California 
Institute of Technology, Pasadena, CA.
------------------------------------------------------------------


NASA ASTROBIOLOGY INSTITUTE PROPOSALS SOLICITED

31 October, 1997


CAN 97-OSS-01 Cooperative Agreement Notice:  NASA Astrobiology 
Institute.  

The National Aeronautics and Space Administration (NASA) is 
interested in receiving proposals under a Cooperative Agreement 
Notice (CAN 97-OSS-01) for participation in a newly forming NASA 
Astrobiology Institute as an innovative way of conducting basic 
interdisciplinary research in the area of Astrobiology; the study 
of life in the universe.  Participation in the program is open to 
all categories of organizations, foreign and domestic, including 
industry, educational institutions, nonprofit organizations, NASA 
centers, and other Government agencies.

The full text of the CAN and all appendices will be available 
electronically via the World Wide Web by selecting "Research 
Opportunities" at:  http://www.hq.nasa.gov/office/oss/ after 
October 31, 1997.  Further information is available from:  Dr. 
Michael A.  Meyer, Research Program Management Division, Code SR, 
Office of Space Science, NASA Headquarters, Washington, DC 20546-
0001; Phone:  (202) 358-0307; FAX:  (202) 358-3097; E-mail:  
michael.meyer@hq.nasa.gov.

This solicitation leading to the award of Cooperative Agreement is 
issued pursuant to title 14 CFR Part 1260 for educational and 
nonprofit institutions and 14 CFR part 1274 for commercial 
organizations.  It will be open for the period through January 30, 
1998.
------------------------------------------------------------------


UB ARCHITECTURE STUDENTS DESIGN HOTELS IN SPACE, INCLUDING ONE 
BUILT INSIDE A 'CAPTURED' ASTEROID

SUNY Buffalo release


BUFFALO, N.Y.--What will hotels be like in the year 2045?  How 
about hotels in outer space?

Two teams of students in the University at Buffalo's School of 
Architecture and Planning explored the possibilities as they each 
designed a "Hotel of the Future" in a Student Design Competition 
conducted by the Association of Collegiate Schools of Architecture 
(ACSA).

The UB projects were among 13 finalists named in the competition, 
which involved 561 students from 99 colleges and universities 
worldwide.

Competitors were encouraged to select remote and unusual locations 
for their hotel.  Options included:  the middle of a city, in a 
remote corner of the Earth, underground, underwater, on top of 
water or in outer space.

Designers were required to use their imaginations to come up with 
a design that would respect its site and surrounding culture, 
incorporate local materials and landscape, satisfy the client's 
program and delight its guests--not an easy task, especially when 
the site is outer space.

The UB teams proposed a modular hotel in orbit 200-250 miles above 
the planet and a hotel constructed in the interior of a "captured" 
asteroid.

Advising the students was Gary Scott Danford, associate professor 
of environmental and organizational psychology in the UB 
Department of Architecture, who assigned the project as part of a 
one-credit course on architectural programming in Spring 1996.

"I am convinced that beyond the novelty of the site (outer space), 
what made these projects finalists was the student inquiry into 
and analysis of technical requirements of the users, guests, staff 
and construction workers in a zero-gravity environment, all of 
which strongly influenced their subsequent architectural designs.

"This project forced the students to recognize that all 
traditional architectural forms were irrelevant and to start from 
scratch without assumptions," Danford added.  "The students also 
learned the importance of communicating, documenting and 
justifying their design decisions."

Students were allowed to form their own teams and worked on the 
project outside of class three hours a week for five weeks.

According to Danford, his students' achievement is particularly 
notable because they only had a fraction of the time their 
competitors had.  "Other students typically took an entire 
semester, or 15 weeks in a 6-7 credit studio, to do this project.  
My students had five weeks in a one-credit course," noted Danford.

He also pointed out that other advisors were typically architects 
rather than environmental psychologists.

Although Danford is not an architect, in 1983 and 1984 he was a 
faculty fellow at the National Aeronautics and Space 
Administration, where he examined long-term habitation of space 
and the psycho-social factors that influence the design of a space 
station.  His knowledge in this area helped the students with the 
technical content of their projects.

"My role," he said, "was primarily to make sure that the students 
acknowledged the difficulty of construction in zero gravity and 
the isolated and hostile environment of outer space, as well as 
the dramatic changes that occur (in zero gravity) in the human 
body, particularly body posture, all of which pose severe 
challenges to conventional architectural design and construction 
techniques."

The entries were judged on quality of design, construction, 
presentation and guest experience.

"Gateway Resort 2045" was the name of the winning design created 
by a UB team consisting of Chris Martell (Portland, Maine), 
Vincent Poon (Brooklyn, N.Y.), Willer Yu (Brooklyn, N.Y.), Anna 
Beresniewicz (Webster, N.Y.), Shantina Moore (Niagara Falls, N.Y.) 
and Elisabette Moreira (Asuncion, Paraguay).  The hotel's 
location:  Lower Earth Orbit inside the Van Allen Belt 
approximately 28.5 degrees from the equator and "flying" at a 
height of 200-250 miles above sea level.

The group incorporated the use of modules to ensure safety in the 
event of a pressure breach, as well as to ease of construction, 
servicing and reconfiguring.  They also altered the size and shape 
of individual rooms and other areas to accommodate new ways of 
sitting, eating and sleeping.

Advanced computer systems with user-friendly voice-recognition 
peripherals were included to monitor guests' physical well-being, 
act as a translating device for the multi-cultured guests and 
offer means of communication with Earth.

The second winning UB design--in which the hotel was constructed 
in an asteroid--was called "Toutatis 4179."  It was the brainchild 
of Jason Benedict (East Syracuse, N.Y.), Karen Chan (Fanling, Hong 
Kong), Darren Hook (Hasbrouck Heights, N.J.), Melissa Morgano 
(Angola, N.Y.) and Scott Nunemaker (Rochester, N.Y.).

What made the project difficult, according to Danford, was the 
need to "capture" a passing asteroid and then excavate the 
interior to create habitable space--in a zero-gravity environment.

The design involved solar-power stations placed in orbit around 
Earth to collect energy from the sun and transfer it to Toutatis 
through microwaves and energy converters.  The students chose to 
inhabit an asteroid because, according to their statement, the 
solid mass provided protection for the guests and because "an 
asteroid in pure form represents all that is natural relevant to 
its environment and only such a spectacle could allow freedom and 
exploration."

Toutatis also was equipped with a museum displaying technological 
advances in space exploration, as well as an escape pod in case of 
the need for evacuation.

Competition sponsors were ACSA, Wimberly Allison Tong & Goo, AT&T, 
Fluor Daniel, Mastercard International, Microsoft and PT Dharmala 
Intiland.
------------------------------------------------------------------

GALILEO:  COUNTDOWN TO EUROPA
by Ron Baalke

2 November, 1997



It is now 4 days and 1 hour to the Galileo spacecraft's closest 
approach to Europa.  A special Countdown to Europa home page is 
now available on the Galileo Home Page:

http://www.jpl.nasa.gov/galileo/countdown/

Launched in October 1989, Galileo entered orbit around Jupiter on 
December 5, 1995, and is currently near the end of its 2 year 
orbital tour around the solar system's largest planet.  Galileo's 
orbital tour consists of 11 elliptical orbits around Jupiter, and 
each orbit (except one) will include a close flyby and gravity 
assist of one of the Galilean moons (Ganymede, Callisto or 
Europa).  In addition to close-up observations of a Galilean moon, 
distant scientific encounters with additional satellites are 
scheduled and Io will be observed at medium range on every orbit.

The first ten orbits have been completed and the next close 
encounter on the 11th and final orbit is scheduled for Europa on
November 6, 1997 20:32 UT.  With a diameter of 3,138 km, Europa is 
slightly smaller than our own Moon an is the smoothest object in 
the solar system.  On Galileo's previous flybys of Europa, ice 
volcanoes were discovered on the icy satellite (none active) and 
probable icebergs were observed for the first time.  Galileo will 
continue its attempt to find evidence of a liquid ocean underneath 
Europa's icy crust and look for signs of active volcanism on the 
moon's young surface.  On the upcoming encounter, Galileo will 
pass by Europa at a distance of 2,042 km, which is 100 times 
closer than Voyager's closest approach.  Also scheduled for the 
Europa 11 encounter are observations of the other satellites of 
Jupiter:  Io, Ganymede, Callisto, Amalthea, Thebe, Metis and 
Adrastea.  Observations of brown barges and aurora on Jupiter are 
also planned as well as a survey of Jupiter's magnetosphere and a 
search for lightning.

Highlights of the Countdown to Europa home page:

* A virtual flyby of Europa with computer-generated approach 
images displayed at the top of the home page, including a 
simulated Galileo view of Jupiter and Europa.  These images are 
updated every 5 minutes.
* Live Doppler plots of Galileo spacecraft radio signal as it 
received on Earth.  Watch the gravity of Europa change the 
frequency of the radio signal in real-time.  The Doppler plots 
will be updated every minute on encounter day (Nov 6).
* The latest Galileo status reports reporting on the Europa 11 
encounter.
* Galileo's current position, updated every minute.  This includes 
the distances from Jupiter, the Earth and Sun, and relative 
speeds.
* Fact sheets and Callisto, Ganymede, Europa, Io and Amalthea.
* A detailed timeline of events and sequences that the spacecraft 
will perform for the Europa 11 encounter.
* Galileo SSI planning images provided by the Galileo imaging 
team.
* Voyager 1 & 2 images of Callisto, Ganymede, Europa and Io.
* Hubble Space Telescope images of the Galilean satellites.
* Pioneer 10 & 11 images of Callisto, Ganymede, Europa and Io.
* Europa flyby animations.

Ron Baalke
baalke@kelvin.jpl.nasa.gov
Galileo Home Page Webmaster
------------------------------------------------------------------


MARS PATHFINDER WINDS DOWN AFTER PHENOMENAL MISSION

JPL release

4 November, 1997


After operating on the surface of Mars three times longer than 
expected and returning a tremendous amount of new information 
about the red planet, NASA's Mars Pathfinder mission is winding 
down.

Flight operators at NASA's Jet Propulsion Laboratory, Pasadena, 
CA, made the announcement today after attempting to reestablish 
communications with the spacecraft over the last month.  With 
depletion of the spacecraft's main battery and no success in 
contacting Mars Pathfinder via its main or secondary transmitters, 
the flight team cannot command the spacecraft or the small rover 
named Sojourner that had been roving about the landing site and 
studying rocks.

"We concede that the likelihood of hearing from the spacecraft 
again diminishes with each day," said Pathfinder Project Manager 
Brian Muirhead.  "We will scale back our efforts to reestablish 
contact but not give up entirely.

"Given that, and the fact that Pathfinder is the first of several 
missions to Mars, we'll say 'see you later' instead of saying 
goodbye," he said.

At the time the last telemetry from the spacecraft was received, 
Pathfinder's lander had operated nearly three times its design 
lifetime of 30 days, and the Sojourner rover operated 12 times its 
design lifetime of seven days.

"I want to thank the many talented men and women at NASA for 
making the mission such a phenomenal success.  It embodies the 
spirit of NASA, and serves as a model for future missions that are 
faster, better and cheaper.  Today, NASA's Pathfinder team should 
take a bow, because America is giving them a standing ovation for 
a stellar performance," said NASA Administrator Daniel S.  Goldin.

Since its landing on July 4, 1997, Mars Pathfinder has returned 
2.6 billion bits of information, including more than 16,000 images 
from the lander and 550 images from the rover, as well as more 
than 15 chemical analyses of rocks and extensive data on winds and 
other weather factors.  The only remaining objective was to 
complete the high-resolution 360-degree image of the landing site 
called the "Super Pan," of which 83 percent has already been 
received and is being processed.  The last successful data 
transmission cycle from Pathfinder was completed at 3:23 a.m.  
Pacific Daylight Time on Sept.  27, which was Sol 83 of the 
mission.

"This mission has advanced our knowledge of Mars tremendously and 
will surely be a beacon of success for upcoming missions to the 
red planet," added Dr. David Baltimore, president of the 
California Institute of Technology, which manages JPL for NASA.  
"Done quickly and within a very limited budget, Pathfinder sets a 
standard for 21st century space exploration."

The Mars Pathfinder team first began having communications 
problems with the spacecraft on Saturday, Sept.  27.  After three 
days of attempting to reestablish contact, they were able to lock 
on to a carrier signal from the spacecraft's auxiliary transmitter 
on Oct.  1, which meant that the spacecraft was still operational.  
They locked on to the same carrier signal again on Oct.  6, but 
were not able to acquire data on the condition of the lander.  At 
that time, the team surmised that the intermittent communications 
were most likely related to depletion of the spacecraft's battery 
and a drop in the spacecraft's operating temperatures due to the 
loss of the battery, which kept the lander functioning at warmer 
temperatures.

Over the last month the operations team has been working through 
all credible problem scenarios and taking a variety of actions to 
try to recover the link with Pathfinder.  With all of the most 
plausible possibilities exhausted, the team plans to continue 
sending commands and listening for a spacecraft signal on a less 
frequent basis.

"Basically we are shifting to a contingency strategy of sending 
commands to the lander only periodically, perhaps once a week or 
once per month," said Mission Manager Richard Cook.  "Normal 
mission operations are over, but there is still a small chance of 
reestablishing a link, so we'll keep trying at a very low level.  
"

Although the true cause of the loss of lander communications may 
never be known, recent events are consistent with predictions made 
at the beginning of the extended mission in early August, Muirhead 
said.  When asked about the life expectancy of the lander, project 
team members predicted that the first thing that would fail on the 
lander would be the battery; this apparently happened after the 
last successful transmission September 27.

After that, the lander would begin getting colder at night and go 
through much deeper day-night thermal cycles.  Eventually, the 
cold or the cycling would probably render the lander inoperable.  
According to Muirhead, it appears that this sequence of events has 
probably taken place.  The health and status of the rover is also 
unknown, but since initiating its onboard backup operations plan a 
month ago, the rover is probably circling the vicinity of the 
lander, attempting to communicate with it.

The rover, which went into a contingency mode on Oct. 6, or Sol 92 
of the mission, had completed an alpha proton X-ray spectrometer 
study of a rock nicknamed Chimp, to the left of the Rock Garden, 
when it was last heard from.  The rover team had planned to send 
the rover on its longest journey yet--a 50-meter (165-
foot)clockwise stroll around the lander--to perform a series of 
technology experiments and hazard avoidance exercises when the 
communications outage occurred.  That excursion was never 
initiated once the rover's contingency software began operating.

Now known as the Sagan Memorial Station, the Mars Pathfinder 
lander was designed primarily to demonstrate a low-cost way of 
delivering a set of science instruments and a free-ranging rover 
to the surface of the red planet.  Landers and rovers of the 
future will share the heritage of spacecraft designs and 
technologies first tested in this "pathfinding" mission.

Part of NASA's Discovery program of low-cost planetary missions, 
the spacecraft used an innovative method of directly entering the 
Martian atmosphere.  Assisted by an 11-meter-diameter (36-foot) 
parachute, the spacecraft descended to the surface of Mars on July 
4 and landed, using airbags to cushion the impact.  The 
spacecraft's novel entry was successful.

Scientific highlights of the Mars Pathfinder mission are:

-Martian dust includes magnetic, composite particles, with a mean 
size of one micron.
-Rock chemistry at the landing site may be different from
Martian meteorites found on Earth, and could be of basaltic 
andesite composition.
-The soil chemistry of Ares Vallis appears to be similar to that 
of the Viking 1 and 2 landing sites.
-The observed atmospheric clarity is higher than was expected from 
Earth-based microwave measurements and Hubble Space Telescope 
observations.
-Dust is confirmed as the dominant absorber of solar radiation in 
Mars' atmosphere, which has important consequences for the 
transport of energy in the atmosphere and its circulation.
-Frequent "dust devils" were found with an unmistakable 
temperature, wind and pressure signature, and morning turbulence; 
at least one may have contained dust (on Sol 62), suggesting that 
these gusts are a mechanism for mixing dust into the atmosphere.
-Evidence of wind abrasion of rocks and dune-shaped deposits was 
found, indicating the presence of sand.
-Morning atmospheric obscurations are due to clouds, not ground 
fog; Viking could not distinguish between these two possibilities.
-The weather was similar to the weather encountered by Viking 1; 
there were rapid pressure and temperature variations, downslope 
winds at night and light winds in general.  Temperatures were 
about 10 degrees warmer than those measured by Viking 1.
-Diversity of albedos, or variations in the brightness of the 
Martian surface, was similar to other observations, but there was 
no evidence for the types of crystalline hematite or pyroxene 
absorption features detected in other locations on Mars.
-The atmospheric experiment package recorded a temperature profile 
different than expected from microwave measurements and Hubble 
observations.
-Rock size distribution was consistent with a flood-related 
deposit.
-The moment of inertia of Mars was refined to a corresponding core 
radius of between 1,300 kilometers and 2,000 kilometers (807 miles 
and 1,242 miles).
-The possible identification of rounded pebbles and cobbles on the 
ground, and sockets and pebbles in some rocks, suggests 
conglomerates that formed in running water, during a warmer past 
in which liquid water was stable.

Engineering milestones of the mission included demonstrating a new 
way of delivering a spacecraft to the surface of Mars by way of 
direct entry into the Martian atmosphere.  In addition, Mars 
Pathfinder demonstrated for the first time the ability of 
engineers to deliver a semi-autonomous roving vehicle capable of 
conducting science experiments to the surface of another planet.

The Jet Propulsion Laboratory manages the Mars Pathfinder mission 
for NASA's Office of Space Science, Washington, DC.  The mission 
is the second in the Discovery program of fast track, low-cost 
spacecraft with highly focused science goals.  The California 
Institute of Technology, Pasadena, CA, manages JPL.
------------------------------------------------------------------


SURVEYOR RESUMES AEROBRAKING, HEADING TOWARD NEW MAPPING ORBIT

NASA release 97-262



NASA's Mars Global Surveyor spacecraft has successfully

resumed aerobraking through the upper atmosphere of Mars, heading 
toward a new science mapping orbit that is the mirror image of its 
original target orbit, project officials announced today.

Aerobraking resumed Nov.  7 with a brief propulsive maneuver that 
changed Global Surveyor's flight path slightly.  A second maneuver 
was performed successfully on Nov.  9, with a third maneuver 
planned for Nov.  12.  These small adjustments at the farthest 
part of the spacecraft's orbit around Mars--known as the 
apoapsis--begin the process of lowering Global Surveyor's orbit 
into the Martian atmosphere more gradually than originally 
planned.

The more gradual aerobraking strategy will lead to a new mapping 
orbit that preserves all of the original scientific objectives of 
the mission.  Selected by the mission's science team, the new 
orbit is essentially just the reverse of the original orbit:  data 
will be taken from the south to the north along the spacecraft's 
orbital track, rather than north to south, and mapping will begin 
one year later than originally planned.

In this new mapping orbit, beginning one-half Mars year 
(equivalent to one Earth year) later than planned, Mars will be at 
a point in its orbit that is directly opposite where it would have 
been in the original mission.  From the spacecraft's point of 
view, the side of Mars that would have been dark will be sunlit 
and vice versa.

"From the perspective of the science instruments, the orbit will 
look just like the original orbit, except that instead of taking 
data from north to south on the sunny side of Mars, Global 
Surveyor will be making its observations in a south to north 
direction in the sunlight," said Glenn E.  Cunningham, Mars Global 
Surveyor project manager at NASA's Jet Propulsion Laboratory 
(JPL), Pasadena, CA.  "The new mapping orbit will take the 
spacecraft down over the Martian equator at 2 a.m.  local Mars 
time during each orbit, rather than the originally planned orbit 
that would have crossed the Martian equator at 2 p.m."

The new mapping orbit will take an additional year to achieve, due 
to both the more gradual pace of aerobraking and a six-month 
hiatus in the spring of 1998, while Mars moves into the correct 
alignment with the Sun for global mapping.  Rather than reaching 
its final mapping orbit in mid-January 1998, and beginning the 
science mission in mid-March 1998, Mars Global Surveyor will 
achieve its final orbital position in mid-January 1999, and 
mapping will begin in mid-March 1999.

"Essentially, we will begin mapping the surface of Mars in mid-
March 1999, during summer in the northern hemisphere," Cunningham 
said.  "Originally we had planned to begin mapping on March 15, 
1998, during summer in the southern hemisphere."

During next year's hiatus, Mars Global Surveyor will remain in a 
fixed, elliptical orbit in which it will pass much closer to the 
surface of Mars during each periapsis--or closest part of its 
orbit around Mars--than it will in the final mapping orbit.  These 
close-range passes are essentially an opportunity for bonus 
science and will provide superb opportunities for data 
acquisition.  The spacecraft's full suite of instruments, 
including the laser altimeter, will be turned on during this time 
to study the planet up close.

"We expect to gain some spectacular new data during this time," 
Cunningham said.  "The spacecraft's orbit will still be elliptical 
during this period, with a duration of between eight to 12 hours, 
but at periapsis, the surface resolution will be much greater, and 
the lighting angles will be excellent."

Mars Global Surveyor's first two aerobraking maneuvers have gone 
well, giving the operations team confidence that the spacecraft's 
unlatched panel will be able to withstand an increased amount of 
pressure as it begins to dip lower into the Martian atmosphere.  
The new pressure level (an average of 0.2 newtons per square 
meter) is about one-third the level of pressure originally planned 
for aerobraking.  Aerobraking is a technique that allows a 
spacecraft to lower its orbit without relying on propellant, by 
using the drag produced by a planet's atmosphere.  The technique 
was first demonstrated in the summer of 1993 during the final 
months of NASA's Magellan mission to Venus.

Although these initial maneuvers have not changed Global 
Surveyor's orbital period significantly, they will soon begin to 
reduce the time it takes the spacecraft to complete one revolution 
around Mars.

"The spacecraft's unlatched solar panel performed as expected 
during the two drag passes we've conducted so far," Cunningham 
said.  "Although we observed some slight movement during the 
passes, the panel returned to its initial position and its 
stiffness did not change.  That performance gives us confidence 
that the mission can proceed without further delay."

A third, five-second burn with spacecraft's small thrusters to be 
performed at 2:30 a.m.  EST on Nov.  12 will lower the 
spacecraft's periapsis by an additional 2.5 miles (four 
kilometers).  With completion of that maneuver, Global Surveyor 
will begin the main phase of aerobraking well inside the upper 
atmosphere of Mars.  During this two-month main phase, the 
spacecraft will be circling Mars every 34.5 hours to start at a 
periapsis altitude of about 77 miles (125 kilometers), with the 
apoapsis starting at 27,500 miles (44,400 kilometers) and 
decreasing with each pass.  The final goal is a 248-mile (400 
kilometer) circular mapping orbit.

If additional problems arise with the aerobraking process, the new 
mission plan will offer the Surveyor team other opportunities to 
reach an elliptical orbit that will satisfy many of the mission's 
science objectives.  These so-called "off-ramps" from the 
aerobraking process, will be detailed in a new mission plan to be 
reviewed by NASA officials in February 1998.

During a press briefing today at JPL, scientists also showed 
stunning new images of layered rock and sediment in the canyon 
walls of Valles Marineris on Mars.  Other images of an ancient 
valley hint at the presence of active sand dunes and dried-up 
ponds.  The new images are available on the Internet at URL:
http://www.msss.com/
or
http://barsoom.msss.com/mars/global_surveyor/camera/images/

Additional information about the Mars Global Surveyor mission is 
available on the World Wide Web by accessing JPL's Mars news site 
at URL:
http://www.jpl.nasa.gov/marsnews/
or the Global Surveyor project home page at URL:
http://mars.jpl.nasa.gov/

Mars Global Surveyor is part of a sustained program of Mars 
exploration known as the Mars Surveyor Program.  The mission is 
managed by JPL for NASA's Office of Space Science, Washington, DC.  
JPL's industrial partner is Lockheed Martin Astronautics, Denver, 
which developed and operates the spacecraft.  JPL is a division of 
the California Institute of Technology, Pasadena, CA.
------------------------------------------------------------------


CORNELL ROVER TO LAND ON MARS IN 2001:  $17 MILLION ATHENA PROJECT 
WILL EXPLORE MARTIAN HIGHLANDS
Cornell University release

ITHACA, N.Y.--Following a real-life space odyssey to Mars in 2001, 
a late-model lander and rover, equipped with a Cornell University 
scientific instrument package called Athena, will roam and study a 
large corridor of the Martian highlands and ancient terrain, the 
National Aeronautics and Space Administration (NASA) announced 
today (Nov. 7, 1997).

The mission, to be launched in April 2001, will seek out the 
geological record of ancient Martian waterways and possible 
biology, according to Steven Squyres, Cornell professor of 
astronomy and the principal science investigator for the Mars 2001 
Lander mission.  NASA is funding the Cornell portion of the 
mission at a cost of $17 million.  James Bell, Cornell senior 
research associate of astronomy, will join Squyres as one of 20 
science team members from the United States, Germany and Denmark 
for the Athena project.

Squyres begins work on the project at NASA's Jet Propulsion 
Laboratory in Pasadena, Calif., on Monday.  "We're starting fast.  
We're going to hit the ground running," he said.

The Athena rover payload on the Mars 2001 Lander/Rover has four 
scientific objectives:

* to provide sharp, color stereo imaging of the planet's surface;

* to determine the fine-scale textural properties of the Martian 
landscape;

* to identify the elements and minerals of the dusty Martian 
countryside;

* to collect and store surface samples in the hope that the 
samples will be retrieved later in the mission.

Autumn has been nothing but gilt-edged for Cornell's role in space 
science history, as today's NASA announcement follows close on the 
heels of other important space projects.

On Oct.  21, NASA announced that Cornell will lead and direct a 
$154 million mission to conduct close-proximity comet fly-bys, 
scheduled for launch in 2002.  On Oct. 31, two Cornell astronomy 
professors announced the discovery of two new moons orbiting the 
planet Uranus.

"We are delighted that NASA has once again affirmed Cornell's 
leadership in space studies by appointing Steve Squyres to lead 
Project Athena," Cornell President Hunter Rawlings said.  "Athena 
is the ancient Greek goddess of wisdom and guardian of the city of 
Athens, of whose enlightened citizens Pericles wrote, 'We throw 
open our city to the world.'  Today, we can say that we open our 
city--our campus--to the stars."

Athena is designed to be larger and to last longer than Sojourner, 
which sent back detailed images of the Martian surface this 
summer.

Rover Athena is part of two Mars Surveyor 2001 missions.  The 
first mission, to be launched in 2001, will be the Mars 2001 
Orbiter, due for launch in March of that year.  Athena is part of 
the second mission, called the Mars 2001 Lander/Rover, which is 
scheduled for launch in April of that year.

Prior to the Mars Surveyor 2001 missions, NASA will launch two 
other robotic Mars missions, now scheduled to blast off in late 
1998 and early 1999, the space agency said.

Both of the Mars Surveyor 2001 missions are part of an ongoing 
series of Mars exploration spacecraft, which began with the 1996 
launches of the Mars Global Surveyor and the Mars Pathfinder 
lander.  All the missions are components of NASA's long-term 
exploration of the red planet, in which two missions are launched 
approximately every 26 months, according to the space agency.

An integrated science team from the Jet Propulsion Laboratory and 
Lockheed Martin Aeronautics, Denver, will develop the missions.

Cornell's Athena rover payload is an integrated suite of 
scientific instruments designed to conduct onsite analyses of the 
surface.  Those instruments include an imager and infrared 
spectrometer, giving the instruments the ability to see through 
dust coatings that normally would obscure spectral analyses of the 
surface.

Athena also will feature an Alpha-Proton-X-Ray spectrometer 
(APXS), a Mossbauer spectrometer and a Raman spectrometer, all of 
which gather mineralogical data.  The microscopic imager will 
reveal surface composition information in detail.

Rather than collect loose pebbles and Martian dust, a low-powered 
mini-corer will drill through the Martian rock to accumulate 
intact samples of rocks and boulders.  The mini-corer can drill at 
an angle and has been demonstrated to cut through dense, basalt-
type formations, according to Squyres.

In addition to Athena, the Mars 2001 Lander will carry an imager 
to take pictures of the terrain during the lander's rocket-
assisted descent to the surface.  The images will render geologic 
information, important for the rover's initial operations and 
traverses by the Athena rover.  NASA said that Michael Malin of 
Malin Space Science Systems Inc., San Diego, Calif., will be the 
team leader for the Descent Imager science team.

PHOTO CAPTION:

[http://www.news.cornell.edu/science/Nov97/Athena.Mars.1.bpf.html]



NASA artist's conception of the Mars rover with the Athena payload 
mounted on the front.

--------------------------------------------------------------------------------

MARS PATHFINDER MISSION STATUS REPORTS


23 September 1997, 11:30 p.m.  PDT

The spacecraft and rover are both in good health today and 
successfully completed their activities.  We did not resolve the 
signal strength problem from yesterday's downlink in which the 
spacecraft signal strength was not as high as expected during the 
final minutes of the transmission session.  In fact, the same 
problem was observed today.  We will continue to investigate the 
cause of this problem.  Fortunately, today we received nearly all 
of the expected data despite this problem.  This included about 
six megabits of science data consisting primarily of super 
resolution images.

The Earth rose this morning on Mars at 2:45 p.m.  and the Sun rose 
at 5:15 p.m.  Pacific Daylight Time.  Today the rover team made 
some necessary changes to the rover's on-board contingency 
sequence.  In addition, Sojourner continued to take APXS 
measurements on the rock "Chimp."

Earth set on Mars at 3:30 a.m.  and the Sun will set 5:15 a.m.  
PDT on September 24th.  The spacecraft will sleep for nearly 16 
hours tonight and will wake up tomorrow morning around 3:00 p.m.  
PST .  We should receive data from the deep space network tomorrow 
starting around 10:00 p.m.  PDT .

Tomorrow's planned activities are for the rover to start off 
towards Mermaid Dune and for the lander to continue with its super 
resolution imaging .  We also plan to continue to take ASI/MET 
weather data.

24 September 1997, 11:30 p.m.  PDT

The spacecraft woke up at 8pm tonight which is 5 hours after Earth 
rise on Mars and 2 hours after sunrise.  All data from the 
spacecraft and rover indicate that they are both healthy.  We've 
received about 2 megabits of data from the Canberra Australia Deep 
Space Network station today during our 1.5 hour downlink session.

We did not experience the problem seen for the last few days 
regarding the spacecraft signal strength.  Although we are not 
completely certain, it is possible that this problem is due to an 
obscuration on the lander.  At a certain time of day on Mars now, 
it appears as if the IMP camera is in the line-of-sight between 
the High Gain Antenna and the Earth.  This is not a significant 
problem, because the geometry will be changing as the days 
progress.

The rover woke up today to the song, "Old Time Rock-N-Roll", 
played by Rover engineer, Howard Eisen.  Howard and the rover are 
longing for the old times of the rolling of the Rover on the 
surface of Mars.  Today the rover did not roll because of the 
completion of the images of the APXS on the rock, "Chimp".  
Tomorrow the rover will begin its journey toward Mermaid Dune.

Earth set on Mars will be at 4:15 AM and the Sun will set at 6:15 
AM PDT on September 25.  The spacecraft will sleep for nearly 16 
hours tonight and will wake up tomorrow at around 8 PM PDT.  We 
should receive data from the spacecraft tomorrow between 10 PM and 
3:30 AM PDT.

26 September 1997, 3:00 a.m.  PDT

The Earth rose over Mars this morning at 4:00 p.m.  PDT and the 
Sun rose at 6:30 p.m.  PDT.

The data received during our 2.5 hour transmit session indicated 
that the spacecraft and rover are in good health.  We received 
less data than expected from the Deep Space Station located in 
Canberra Australia due to bad weather.  Although we expected to 
drive the rover today, we were not able to do so due to critical 
Mars Global Surveyor operations which occurred at the same time 
and required extra DSN support.

So, we contacted the spacecraft after it woke up at 3:00 p.m.  
PDT, made sure it was healthy and then verified that the expected 
super resolution imaging data and ASI/MET measurements were being 
collected.

We played the rover wakeup song "Slud" by Jive of Clay, reminding 
us of what the area near our landing site was like 4.5 billion 
years ago.  Earth set on Mars will be at 4:45 am and the Sun will 
set at 6:30 a.m.  PDT on September 26th.

The spacecraft will sleep from 5:17 a.m.  and until 9:00 p.m.  
tomorrow PDT.  We should receive data from the spacecraft from 
between 10:00 p.m.  and 3:30 a.m.  this time tomorrow.  We are 
planning for the rover to drive towards toward Mermaid Dune.

29 September 1997, 12:45 PM PDT



For the past few days, we have been having difficulty 
communicating with the Pathfinder spacecraft and Sojourner rover.  
Although we have expected the spacecraft to attempt to communicate 
with us, we did not receive the expected signal.

Today we will attempt to understand what the spacecraft problem is 
by using the Canberra Deep Space Network station to uplink 
commands to Pathfinder that will cause us to give us a beacon 
signal from the low-gain antenna.  We will also attempt to 
initialize the high-gain antenna and send down engineering data 
that will help us diagnose the problem from the last few days.

Although we don't specifically know the problem, we do believe it 
is associated with the expected degradation of the Pathfinder 
battery.  It is possible that the lander is now operating only on 
solar power, and we will need to adjust the operations to support 
this.  Understanding how to do this and also how the spacecraft 
operates in this new mode are our goals for the next few days.

October 1, 1997

After experiencing difficulties in communicating with the Mars 
Pathfinder spacecraft for the past three days, the operations team 
was able to reestablish a brief two-way communications session 
Tuesday using the lander's auxiliary transmitter.  Receipt of this 
beacon signal indicated that the spacecraft is still operational.

The team began having communications problems with the spacecraft 
on Saturday, Sept.  27.  These problems could be related to 
degradation of the spacecraft's battery.  The last successful data 
transmission cycle from Pathfinder was completed at 3:23 a.m.  
Pacific Daylight Time on Sept.  27, which was Sol 83 of the 
mission.

No signal was received from the spacecraft on the next Martian 
day, Sol 84, which began in the evening of Sept.  27.  The team's 
transmission session began at 11:15 p.m.  PDT.  The lack of a 
signal, at that time, was thought to be caused by a possible 
computer reset incident, ground system problem or low voltage 
condition.  A reset or a low voltage condition, caused by the 
aging of the battery, would cause the spacecraft sequence to 
automatically stop and not execute its planned communication with 
Earth.

The team attempted to communicate with the spacecraft again on 
Sept.  29 (Sol 85) and Sept.  30 (Sol 86) with no success.

Tonight, on Sol 88 of the mission, the team will use the auxiliary 
transmitter again to attempt to acquire engineering data that will 
help them assess the cause of the communications problem.  
Meanwhile, the rover, which receives its instructions from Earth 
via the lander, is currently running a contingency program which 
has instructed it to stand still rather than begin its trek around 
the lander.

The team will repeat these activities on subsequent days and 
attempt to receive telemetry that will give them more information 
about the health of the lander and rover.

If Pathfinder operations do not return to normal tonight, a Mars 
Pathfinder team representative will provide an update on the 
situation at the beginning of the planned Mars Global Surveyor 
science news briefing at 9 a.m.  PDT on Thursday, Oct.  2.

3 October 1997



The Mars Pathfinder spacecraft team has been experiencing 
communication problems with the lander spacecraft on Mars.  The 
last successful data transmission cycle was completed Saturday 
morning, September 27, 1997 at 3:23 am (sol 83).

On September 27, at 11:15 pm, (sol 84) no signal was received.  
The spacecraft was powered on at 2:00 am local Mars time to 
perform early morning weather measurements and sky images.  The 
lack of a signal, at that time was thought to be caused by a 
possible reset, ground system problem or low voltage condition.  A 
reset or a low voltage condition, caused by the aging battery, 
would cause the spacecraft sequence to automatically stop and not 
execute its planned communication with Earth.

On September 29 at 1:30 am (sol 85) the team attempted to command 
the spacecraft to send a carrier signal to Earth over the low gain 
and high gain antenna.  Neither signal was received.

In the early morning of September 30 (sol 86), the team again 
attempted to command the spacecraft to send a carrier signal to 
Earth over the low gain antenna.  This attempt was done at Mars 
local noon in order to ensure maximum power on the solar arrays in 
order to power the spacecraft transmitter .  No signal was 
received.  At this point a preliminary assessment was made of 
possible problems.  As in the past, loss of communication can be 
caused by problems with the ground system, flight software and/or 
flight hardware.

On early Wednesday morning, October 1, (sol 87), assuming a 
possible hardware problem, the team commanded the spacecraft to 
switch to its auxiliary transmitter.  At first no signal was 
received but at approximately 4:23 am, a signal was received that 
lasted for about 20 minutes.  The team also attempted to power on 
the secondary string of the main transmitter but no signal was 
seen.

Thursday morning, October 2, (sol 88), the team attempted to get 
digital data from the auxiliary transmitter.  During the beginning 
of track the spacecraft auxiliary transmitter signal was seen 
again.  The signal turned off at 11:30 local solar time on Mars 
indicating that the spacecraft computer had enough power to wake-
up and turn off the transmitter.  Because of the late wake-up 
there was no time to attempt to receive digital data from the 
spacecraft.  At this point the team assessed that the spacecraft 
may be seeing extra loads on the bus resulting in late wake-up 
times.  Since this could be related to a battery failure, commands 
were sent to put the spacecraft in a mode where it does not use 
the battery and takes it off-line.  It is not clear whether these 
commands were received.

October 3, (sol 89), the team once again attempted to get digital 
data on the auxiliary transmitter.  No data was received.  
However, the time of day in which it was necessary to try and send 
data due to tracking station elevation requirements may have been 
too early for the spacecraft to have been awake.  A later attempt 
was made to send and activate a sequence on the spacecraft, which 
put the Pathfinder in the safest state possible for a potential 
non-operational battery.  There was no signal indicating that 
these commands executed on the spacecraft.  The problem of not 
seeing this signal could have been ground station related.

The rover continues to be in a contingency state.  Sojourner will 
do nothing until Sunday, October 5 (sol 91) and then will begin to 
drive in an arc around the lander.

The team continues to investigate a number of possible scenarios.  
Since so little information is currently available from the 
spacecraft the number of possible scenarios is large.  However, 
since the spacecraft battery has exceeded its expected lifetime by 
a factor of 3, scenarios associated with the degradation of the 
battery are probably most likely.  Learning how the spacecraft 
operates without the battery is something the team is in the 
process of doing.

Although the Pathfinder mission has extended far beyond its 
expected lifetime, the team is currently doing everything possible 
to attempt to get back on schedule with Pathfinder's extended 
mission.

15 October 1997, 3:00 p.m.  PDT

Today again we attempted to up link commands to the spacecraft 
that would turn on the transmitter.  However, we were 
unsuccessful.  Tomorrow we will resume our attempts to command the 
spacecraft.  Our team is continuing to investigate the problem in 
an effort to better understand what is occurring on board the 
spacecraft.

16 October 1997, 4:00 p.m.  PDT

After making some changes in our commanding strategy yesterday, 
commands were sent to the Sagan Memorial station which should have 
resulted in a signal from the spacecraft's low gain antenna being 
received on Earth.  The signal was expect at 1:15 this afternoon, 
but was not seen.  The spacecraft was then commanded to send two 
additional signals to Earth today using both its primary and 
auxiliary transmitters, but neither signal was received.  The last 
verified signal we received from Pathfinder was nine days ago on 
Sol 93.  Tomorrow's plans include the anticipated use of the 70 
meter station at Goldstone California.  Sol 103 will mark the 
first use of our new temperature models for both commanding the 
spacecraft and receiving a signal from the spacecraft over its 
auxiliary transmitter.

The spacecraft team remains optimistic that the Sagan memorial 
station is good health and that our current difficulties can be 
traced to lower than normal operating temperatures.

17 October 1997, 4:00 p.m.  PDT

Today we attempted to make contact with Pathfinder using the 70 
meter station in Goldstone California.  We commanded the 
spacecraft to turn on the auxiliary transmitter, but unfortunately 
we did not see any downlink signal.

Due to commitments to the Galileo mission we moved our operations 
to the 34 meter antenna and commanded the spacecraft to turn on 
the SSPA transmitter.  The SSPA is a backup transmitter in 
addition to our primary and auxiliary transmitters.  
Unfortunately, we did not receive any signal during this second 
attempt.

We will continue with our efforts to reestablish contact with 
Pathfinder and will promptly post any favorable developments.

October 29, 1997



Mars Pathfinder's operations team is continuing daily efforts to 
reestablish communications with the lander.  Over the last month 
the team has been working through all credible problem scenarios 
and taking a variety of actions to try to recover the link with 
Pathfinder.  They plan to continue sending commands to the 
spacecraft for another week before shifting to a contingency plan 
of less frequent commanding and listening.

During the past month, the team has investigated a variety of 
scenarios that could explain why the Pathfinder lander has not 
sent telemetry to Earth since September 27.  Since that time, 
ground stations have detected a carrier signal from the lander on 
two occasions, but on each attempt following the receipt of the 
carrier signals they were not able to reestablish a link, and 
therefore no digital data was received to enable determination of 
the spacecraft's condition.

The team initially investigated the possibility that the lander's 
battery had failed.  This scenario would have resulted in 
spacecraft clock uncertainties and unknown spacecraft power 
conditions due to the lander only operating on solar power.  They 
then investigated the possibility that, because the lander's 
transmitter had been turned off for many days, the lander's 
temperature had dropped to a range between -50 and -30 C (-58 to -
22 F), some 20 to 40 degrees C (about 35 to 70 degrees F) colder 
than previous operating temperatures, causing its radio receiver 
to shift away from its normal frequency range.

Currently the team is sending commands to the lander to 
investigate the possibility that the spacecraft's flight computer 
is not operating normally.  "Under this scenario, the thought is 
that perhaps the computer is not booting up fully," said Mission 
Manager Richard Cook.  "The team is sending resets to the lander 
at various times of the day before we attempt to send other 
commands."

All scenarios are expected to have been fully investigated by end 
of day on Tuesday, November 4.  If the team does not reestablish 
contact by then, said Project Manager Brian Muirhead, they plan on 
shifting to a contingency strategy of sending commands to the 
lander only periodically, perhaps once a week or once per month.  
"The normal extended mission would be over, but there is still a 
small chance of reestablishing a link, so we'll keep trying at a 
very low level," Muirhead said.  "Of course the science team will 
continue to process, catalog and understand the large volume of 
science data we have received, which will keep us very busy for 
several months."

Although the true cause of the loss of lander communications may 
never be known, recent events are consistent with predictions made 
at the beginning of the extended mission in early August.  When 
asked about the life expectancy of the lander, project team 
members predicted that the first thing that would fail on the 
lander would be the battery; this apparently happened after the 
last successful transmission September 27.  After that, the lander 
would begin getting colder at night and go through much deeper 
day-night thermal cycles.  Eventually, the cold or the cycling 
would probably render the lander inoperable.  According to 
Muirhead, it appears that this sequence of events may have taken 
place.  The health and status of the rover is also unknown, but 
since initiating its onboard backup operations plan three weeks 
ago, it is probably in the vicinity of the lander attempting to 
communication with the lander.

At the time the last telemetry from the spacecraft was received, 
Pathfinder's lander had operated nearly three times its design 
lifetime of 30 days, and the Sojourner rover operated 12 times its 
design lifetime of seven days.  Since its landing on July 4, 1997, 
Mars Pathfinder has returned 2.6 billion bits of information, 
including more than 16,000 images from the lander and 550 from the 
rover, as well as more than 15 chemical analyses of rocks and 
extensive data on winds and other weather factors.  The only 
remaining objective was to complete the high-resolution 360- 
degree image of the landing site called the "Super Pan," of which 
83 percent has already been received and is being processed.
------------------------------------------------------------------

MARS GLOBAL SURVEYOR FLIGHT STATUS REPORTS


Saturday, 27 September 1997



Aerobraking operations on the Mars Global Surveyor mission 
continue to proceed smoothly.  As of today, the spacecraft has 
completed nine revolutions around the red planet, including six 
aerobraking passes through the upper Martian atmosphere.  Each of 
these atmospheric passes took place at the start and low point of 
the orbit as Surveyor zipped across the sky at altitudes scarcely 
greater than 72.1 miles (116 km).

At the start of aerobraking slightly more than one week ago, the 
high point of Surveyor's orbit occurred at an altitude of 33,570 
miles (54,025 km).  Since then, air resistance from the 
atmospheric passes has slowed the spacecraft by an average of 2.2 
mph (1 meter per second) on each orbit.  The result is that the 
orbit's high point has dropped by 1,050 miles (1,690 km).  Over 
the next four months, aerobraking will reduce the high-point 
altitude all the way down to 280 miles (450 km).

Dr. Richard Zurek of the Surveyor science team reports that the 
thickness of the Martian atmosphere continues to run slightly 
higher than predicted by current models.  Because a thicker 
atmosphere will result in more stress on the spacecraft during 
aerobraking, both the navigation and atmospheric science teams are 
currently studying possible changes to the baseline plan.  
However, no major changes are expected because Surveyor was 
designed to tolerate up to a 70% increase in atmospheric 
thickness.

In other news this week, minor wobbling on the spacecraft's solar 
panels caused the pointing control system to off-point Surveyor's 
high-gain antenna by slightly more than two degrees from the 
direct line to the Earth.  The flight team fixed the wobbling by 
commanding the solar panels into a stable position.  Then, the 
pointing discrepancy was corrected by allowing Surveyor to scan 
and lock-up on reference stars in deep space.  These distant stars 
serve as fixed reference points that allow the spacecraft to 
determine its proper pointing orientation relative to the Earth 
and Sun.

After a mission elapsed time of 324 days from launch, Surveyor is 
165.28 million miles (265.99 million kilometers) from the Earth 
and in an orbit around Mars with a period of 42.75 hours.  The 
spacecraft is currently executing the P10 command sequence, and 
all systems continue to be in excellent condition.

16 October, 1997


Mars Global Surveyor arrived at Mars on the evening of September 
11th and achieved a very precise 45 hour long elliptical orbit 
around the planet.  During the spacecraft's third closest approach 
to the planet, the MGS science instruments had the opportunity 
acquire a significant amount of new information relative to the 
surface, atmosphere and interior of Mars.  Among these new 
findings is the observation that the northern hemisphere area 
called Elysium is extremely flat, and that there are strong 
remnant magnetic fields near the surface rather than a global 
magnetic field like the Earth's.  (See http://mars.jpl.nasa.gov)

You may have heard that MGS has encountered some difficulty with 
aerobraking and that's true.  After twelve aerobraking drag passes 
we've pull up out of the Mars atmosphere to assess the unexplained 
motions of one of the solar panels that we've observed and to be 
sure that the spacecraft is safe and that we preserve our ability 
to acquire more great science data at Mars.  We've decided to take 
a two week hiatus from aerobraking to do this.  The big effect 
from the time lost due to the hiatus is that we will use a 
different mapping orbit later on, and we are working on defining 
what that orbit will be.

In the mean time, we have taken opportunity afforded us by the 
hiatus in aerobraking to take a lot more significant science data 
at each periapsis pass.  The Laser Altimeter has been turned back 
on and the Mars Orbiter Camera, and Thermal Emission Spectrometer 
will have great opportunities for science acquisition.  The 
current periapsis altitude is two times closer to the surface of 
Mars than the altitude would be during the originally planned 
mapping orbit so the surface resolution is much greater.

The spacecraft, except for the uncertainty concerning the -Y solar 
panel, and all its instruments are working exceptionally well, and 
we continue to have great expectations for the discoveries that 
this mission will return.

MGS...  the adventure continues.

Read on if you want more details on the situation:

The Mars Surveyor Operations Project began, on September 16th, 
moving the lowest point of the MGS's orbit from 250 km (155 miles) 
down into the Martian atmosphere in order to begin aerobraking.  
Aerobraking is the process that uses the drag on the spacecraft 
caused by skimming through the top of the atmosphere to reduce the 
period of the orbit.  Aerobraking worked just fine!  After twelve 
passes through the upper atmosphere, we reduced the orbital period 
from its initial 45 hours down to 35 hours on the way to the 
target of 2 hours.

You may recall that when MGS was launched, the -Y solar panel did 
not completely deploy and latch properly.  It ended up about 20 
degrees away from being folded out completely flat.  After a lot 
of analysis and test, we determined the best way to do 
aerobraking, which uses the solar panels to provide most of the 
drag surface area, was the turn the -Y panel around.  Thus, the 
atmospheric drag pressure would push on it during aerobraking so 
that we were compressing the small piece of metal that we believe 
is trapped in the solar panel's hinge joint.  Then, as the drag 
pressures on the panel increase as we got deeper into the 
atmosphere, the panel might move further toward the fully folded 
out position and even latch.

On Tuesday, October 1st, at periapsis or closest approach to Mars 
number 12 where the altitude was 110 km (68 miles), we observed 
the panel move about 14 degrees closer to fully unfolded - good!  
Then, on Monday, October 6th, we had an aerobraking drag pass 
(periapsis 15) where the Martian atmosphere became more dense than 
we had expected for that orbit, although well within the 
capabilities of the spacecraft, and we observed the panel move 
past where we thought it should latch and stay past that position 
by about one degree - not so good!

Atmospheric density variations like observed in periapsis 15 are 
expected as the seasons change on Mars, and it is probably not the 
result of a great dust storm.  Our flight operational process is 
designed to accommodate these kinds of variations, and so, to 
reduce the dynamic pressure that the atmosphere puts on the solar 
panels, we moved the spacecraft's orbit up 11 km (7 miles) to 121 
km (75 miles), to where we thought the pressure would be fairly 
light on the panel.  That would also give us a few days to 
understand why the panel might have moved past its latch point.  
As it turned out, the pressure was small as we expected, but the -
Y solar panel continued to show us some unexpected motion during 
the next two drag passes.  There has never be any concern about 
the electrical power that the panel produces.

Thus, on Saturday evening, October 11th, we decided to take the 
spacecraft completely out of Martian atmosphere because we are 
concerned that we don't know why the panel moves as it does and we 
were concerned that we might have some kind of life limiting 
mechanism involved.  The closest point to Mars is now about 172 km 
(107 miles) and the orbital period is about 35 hours.

We are taking a two week hiatus from aerobraking, and in the 
process we have forfeited our ability to reach the orbital 
conditions that would result in the sun synchronous circular 
mapping orbit with an equator crossing at 2 pm local solar mean 
time.  There are, however, other orbital conditions that we can 
reach that will yield exceptional science return from Mars.

During the hiatus, the Mars Surveyor Operations Project team, at 
JPL and Lockheed Martin Astronautics, is studying the observed 
motion of the solar panel, and will understand how the original 
launch failure model must be modified to accommodate the new 
motion.  With that information, we will then plan how to start 
aerobraking again in a configuration that will not stress the 
panel, and given the intensity of aerobraking that is possible, 
we, with the MGS science investigators, will determine the best 
mapping mission to target for.  The 2 pm orbit was a compromise 
among the science investigators.  We will work for another 
compromise orbit that yields the best results for whatever orbital 
capabilities we can achieve.  In the best case, it will be a 
circular orbit at some other local time.  In the worst case, it 
will be an elliptical orbit with a period of about 16 hours.

We are planning on a Monday, October 27th, a decision milestone on 
the plans for and safety of returning to aerobraking.

Status report prepared by:
Office of the Flight Operations Manager
Mars Surveyor Operations Project
NASA Jet Propulsion Laboratory
California Institute of Technology
Pasadena, CA 91109
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End Marsbugs Volume 4, Number 15



