TES News
November 1993, Volume 2, No. 4
Thermal Emission Spectrometer Project
Mars Observer Space Flight Facility
Department of Geology, Box 871404
Arizona State University
Tempe, Arizona 85287-1404, U.S.A.
To Mars Orbit In '97? - Life after Mars Observer
Mars Observer Lost
Communication with the NASA
Mars Observer spacecraft
was lost on Saturday, August 21,1993. All attempts to reestablish
the communication line were unsuccessful. The Thermal
Emission Spectrometer (TES) group at Arizona State University
(ASU) held an open house on August 24th, the day Mars
Observer was to go into orbit about the Red Planet. Over 100
visitors came from all over Arizona to see if NASA would hear
from the spacecraft on this day. Unfortunately, the results were
disappointing.
The
NASA Jet Propulsion Laboratory (JPL)
Mars Observer
Project Office has instructed the mission's Principal Investigators
to continue operating under the existing Mars Observer
infrastructure with the hope of launching some or all of the Mars
Observer science payloads on future missions. ASU's Dr. Philip
Christensen, the TES Principal Investigator, says that although
some downsizing of the TES operations team will occur, the TES
research group will remain largely intact in order to help prepare
for a new mission to Mars. Mars Observer was the first complete
loss of a U.S. interplanetary spacecraft. According to Christensen,
"There are no rules for the situation NASA has found
itself in."
NASA Investigates
The NASA Administrator, Daniel Goldin, has appointed
two separate committees, one to investigate possible explanations
for the loss of contact with Mars Observer and another to
report on the most likely opportunities for rebuilding the Mars
Observer science instruments and sending them on to Mars. The
results of both investigations are to be forwarded to Goldin by the
end of November 1993. The panel studying options for new
missions to Mars has been instructed to show how these missions
will fit in with NASA's other plans to send small landers to Mars
in the later half of the decade. The new Mars missions will likely
consist of spacecraft that are smaller than Mars Observer, and
may require spreading the original contingent of science instruments
over two or more different spacecraft.
One important constraint on the design of new Mars missions
is the fact that Mars and the Earth only come into proper
alignment for launch approximately every 26 months. Any new
mission will have to be planned in such a way that it coincides
with one of these launch windows." The next launch window is
in October 1994. A spacecraft takes 11 months to reach Mars,
thus a 1994 launch would mean a September 1995 arrival.
Congress provided $10 million for Mars missions in Fiscal Year
1994, thus there is not enough money, nor time, for the U.S. to
build a new spacecraft and send it to Mars in 1994. The next
launch opportunities occur in November 1996, with an October
1997 arrival at Mars, and December 1998. A 1998 launch would
put a spacecraft into orbit around Mars in November 1999.
Another launch window occurs in January 2001.
If you could visit Mars...
...where would you want to explore? This is the caldera at the top of
Pavonis Mons, a huge shield volcano on the martian equator.
The crater you see is 45 km (28 miles) across and formed by
the withdrawal of magma deep beneath the volcano. Geologists
are interested in volcanoes because they might provide clues to the
composition of the deep crust and mantle of Mars. Photograph
from the Viking 2 orbiter taken in 1976.
Or maybe you would want to land...
...on Mars and take a closer look. Above is an image
from the Viking 1 lander taken in 1977.
Building A New TES
Christensen says that his team is proceeding under the
assumption that another TES will be flown on the next U.S.
mission to Mars. Thus, the TES team is moving ahead with the
steps necessary to have a TES ready for a possible 1996 launch.
While it has been rumored that a new Mars Observer spacecraft
can be built from existing "spare parts," TES systems engineer,
Greg Mehall, is quick to point out that the issue is more complex
than simply assembling these parts. Although spares do exist for
many components, there are no backups for the most epensive
and complete parts of Mars Observer and its instruments. While
work progresses on these so called long-lead items, thought is
also being given to some minor-designs of the TES . "There are
things we would change based on experience," said Christensen.
When construction of a new TES begins, it will be assembled
(like the first TES) at the Hughes Santa Barbara Research Center
in Goleta, California.
Other Missions To Mars?
In addition to the prospects for a new Mars Observer-type
mission, there are several other Mars spacecraft being planned or
built. The first, Mars 94, consists of a set of orbiters,
landers, and
penetators (which would dig into the martian soil). Mars 94 is
an international program being assembled in Russia for launch
from Kazakhstan in October 1994. However, because of financial
difficulties, it is possible that this mission will be delayed to
a 1996 launch. Russia has also been working on a mission called
Mars 96. Japan has plans for a spacecraft that will fly past Mars
in 1997. Also for 1996, the U.S. is planning to send a small
lander, bearing an even smaller robotic rover, called MESUR
Pathfinder. MESUR stands for Mars Environmental SURvey.
The Pathfinder mission is designed to test the concept of sending
small landers to the planets. A whole series of MESUR landers
is in the planning stages for U.S. Mars exploration in the 1998 -
2005 time frame.
Mini TES
The MESUR landers are planned to be small, perhaps only
a meter wide at the base. In addition, many of the Mars orbiter
concepts being considered to replace Mars Observer are also
small. Thus, a challenging aspect of designing a future TES will
be the interfacing of such an instrument with new spacecraft
designs. An example of a smaller, less expensive spacecraft is
Clementine, which will be sent to map the Moon and the asteroid
Geographos in January through March 1994. Clementine was
designed and built by the Ballistic Missile Defense Organization
(formerly known as "SDI" or "Star Wars"). The Clementine
spacecraft measures approximately one cubic meter, not much
larger than the TES flown on Mars Observer. If spacecraft the
size of Clementine are the wave of the future, then spacecraft
instruments will have to be made smaller. An exciting prospect lies
in making miniature versions of the TES. Christensen and
Mehall have begun discussing ideas for a new instrument which
would be half the size of the original TES, would require half the
power, and would still produce the same level of scientific return.
The proposed instrument will be the size of a soda can. Because
it would be initially designed for the MESUR landers, it has been
called "Mars Surface TES," or, informally, "Ms. TES."
ASU TES Staff and Students Look Ahead
How has the Mars Observer loss affected the rest of the ASU
TES group? The TES computer programming staff is continuing
to develop user-friendly software which allows scientists to view
existing Mars data for areas of interest on the marlian surface and
to plan future observations. The software applications being
developed could also be applied to the collection and evaluation
of data from
NASA's Earth Observing System
satellites which
will begin operations in 1998.
ASU geology graduate students involved with TES have had
to reconsider dissertation topics. For example, where a particular
thesis might have required new data from the TES instrument,
several students are now concentrating more on laboratory and
field studies which may have future application to Mars data.
Several graduate research assistants will likely complete their
dissertations somewhat earlier than anticipated. Meanwhile, the
ASU Thermal Emission Spectroscopy Lab is continuing to
assemble a spectral library of Earth's minerals and rocks. This
activity employs several undergradute science students as well as
graduate assistants.
Mars TES Education Program Continues
The Mars TES Educational Program remains alive and well.
This fall, more than 600 K-12 students have visited the TES
Facility at ASU. Education personnel have emphasized a context
in which students can understand the loss of Mars Observer and
gain a greater appreciation of why we "do science" and explore
the universe against sometimes difficult odds. TES personnel are
also busy assembling educational resource materials that are
being made available to teachers who visit the TES Facility.
Educators who have a demonstrated interest in Mars science will
have an opportunity to browse and evaluate educational materials
relating to Mars and the Solar System. Resources include
books, magazines/journals, posters,
slide sets,
video tapes, maps,
and Mars globes. While most materials are available for inspection
only, a few items may be borrowed by educators for use in
their classroom. The TES team will hold its third K-12 Educators'
Workshop
in February, 1994. For more information, call
the ASU TES Project Office, (602) 965-1790.
Recent Articles
Begley, S., "Lost in Space," Newsweek, September 6, 1993.
Benningfield, D., "The Odd Little Moons of Mars," Astronomy,
December 1993.
Boyer, W. H., "Alls Quiet on the Martian Front," Final Frontier,
November-December 1993.
Cook, W. J., "The Invasion of Mars," U.S. News & World
Report , August 23, 1993.
Lemonick, M. D., "Lost in Space," Time, September 6, 1993.
McKay, C. P., "Did Mars once have Martians?," Astronomy,
September 1993.
A new TES NEWS is available every 3 to 6 months.
This newsletter may be copied for educational
purposes only. A hardcopy version of TES NEWS
can be obtained by visiting the Mars TES Facility
on the campus of Arizona State University.
Please share or recycle all hardcopies of this
document.
Text by:
Steve Schmidt &
Kenneth S. Edgett
Typeset by:
Kathy Patoni & Kenneth S. Edgett Original Text:
November 12, 1993 This On-line version: January 20, 1994
