Live From Mars was active July 1996-December 1997.

UPDATE # 48 - August 1, 1997

PART 1: Rebroadcast of July 6 & 9 LFM Programs: Starting Aug. 1
PART 2: Updated WebChat Schedule
PART 3: Mars Writing Contest: Deadline Aug. 15
PART 4: Mars Global Surveyor Journal: Why I Lie Awake at Night
PART 5: Mars Pathfinder Update
PART 6: Subscribing & Unsubscribing: How to do it!


NASA TV will rebroadcast the July 6 and 9 Live From Mars programs
starting this week! Program 3A, "Touchdown!" will be aired Friday,
Aug. 1 at 1 p.m., Eastern. Program 3B, "Touchdown +6!" will run Monday,
Aug. 4 at 1 p.m., Eastern.

NASA TV is broadcast on GE-2, transponder 9C, C-Band, located at 85
degrees west longitude. The frequency is 3880.0 MHz. Polarization is
vertical and audio is monaural at 6.8 MHz.


Tuesday, August 5, Time: TBD (most likely at noon), Pacific Daylight,
David Mittman
From preparing for Pathfinder's landing and planning rover's activities
the day after landing, to writing commands for the spacecraft, David does
double duty on the Pathfinder team as mission planner and flight
controller. Come prepared to the chat by first reading David's bio and
journals at:

Tuesday, August 12, 9:30 a.m., Pacific Daylight, Steve Lee
As a member of the Hubble Space Telescope Mars Team, Steve is the surface
expert. He is interested in the interaction between the surface and the
atmosphere on Mars. Steve's bio will be available soon at

Monday, August 18, 10 a.m., Pacific Daylight, Mike Mellon
Mike is a planetary geologist. His work focuses primarily on studying
martian geology and climate, including, as a central link between these
two, water. In his work, Mike investigates where water on Mars could be
located and what geologic evidence can tell us about the planet-wide
distribution of water. Mike also studies how water is related to the
martian climate and how the climate changes over time. Be sure to read
Mike's bio before his chat at:

To participate in the WebChats, RSVP at least 24 hours in advance to
reserve a space for yourself. Send RSVP to: You
will receive confirmation of your registration and a password to enter the
chat room. If the chat rooms are full by the time you register, you can
still participate by watching the chat from the Observe Room at:


[Editor's note: Reprinted from the Los Angeles Times newspaper.]

Would you go?

Ok, imagine this: The powers-that-be have decided that it's time to
colonize Mars and they're looking for volunteers. Interested? Why? Why
not? Let us know, in 50 words or less, by writing to "Life on Mars," c/o
Life and Style, Los Angeles Times, Times Mirror Square, Los Angeles, CA
90053 (fax: 213-237-4888). No phone calls, please, but be sure to include
your daytime and evening numbers! Submissions must reach us by Aug. 15,
and sorry, cannot be returned. 


[Editor's note: Phil Christensen is the principal investigator of the
Thermal Emission Spectrometer instrument onboard Mars Global Surveyor. He
also has a passion for geology and is a geology professor at Arizona State
University in Phoenix.]

by Phil Christensen

August 1, 1997
I'm still having nightmares. I think they are my subconscious telling me
"Hey pal, these are all the things you need to be getting done in the next
42 days before we go into orbit around Mars." For five years now I've had
a running list of the top 20 things that need to get done, but usually
there are 40 things listed!

With about six weeks left before Mars Global Surveyor intercepts Mars on
September 11, we on the Thermal Emission Spectrometer (TES) team are
frantically worrying about finishing the absolutely crucial things on that
list. The main thing we're struggling with now is the science analysis
software and how we're going to handle the huge volume of data (about
100,000 spectra a day!). There are two problems. First, we've never flown
an instrument anything like TES before and we've spent the last five to 10
years trying to figure out how to analyze the data and what we would do
with it. In the old days we would've had the data and played with it for a
year before going public, and after six months to a year we would've
started to write science papers. In the current environment there'll only
be three or four days before someone will come to us and ask where should
we land the next rover? Where are the neat rocks? Where should we look for

The very enthusiasm about Mars has upped the ante in terms of the
real-time analysis of data. The Pathfinder team is experiencing this first
hand. "You've had the picture now for 20 minutes, what can you tell us
about the history of Mars?" Now that everything's up on the Internet
almost as fast as we receive it, you've got people calling in saying,
"Hey, I see a rock over there on the horizon that looks kind of rounded.
Why?" And the poor science team that's been up for 24 or 48 hours hasn't
even looked at that picture yet! The pressure to do "instant science" is

Back in November TES took its first test image of Earth. It wasn't really
an image as Earth was smaller than one pixel in our instrument, but we got
a beautiful spectrum of the Earth (that we've already written a paper
about)! TES detected ozone and carbon dioxide in water vapor, which if you
were searching for planets that had life, you would hone in on Earth. But
in terms of further developing TES's science analysis system software
techniques, it didn't help much because Earth was so tiny and the total
number of spectra that we got with Earth in them were 15, so I processed
them by hand. When we get into orbit around Mars, we'll get 100,000
spectra a day... that's why I lay awake at night. 

In the spectroscopy world a grad student goes into the lab and takes 20
spectra of 20 rocks and ponders them for a month. The spectra are looked
at one at a time, while noting the subtleties and details. No one has ever
had to deal with 100,000 spectra a day. If I can process one spectrum at a
time by hand, there's no conceptual reason why a computer can't process
100,000! The hard part is believing the numbers the computer is throwing
back at you, and none of us wants to do that! We want to be left alone for
a year to digest all the spectra and figure out the errors and the
problems before we have to get up and announce our results!

Once Mars Global Surveyor begins transmitting TES data back to Earth,
we're going to have to go public almost instantly. Our strategy will
probably be to take our data, pick three of the wavelength bands and
process them into a color image. Our brains are really good at identifying
a blue pixel, a yellow pixel and a blob of orange pixels because they all
look different. We'll then pull up the 10 spectra for each of those areas
and then we'll be back in the old mode of doing 10 at a time by hand! But
now the problem is, we're throwing away 999,990 while we focus on the 10!

If you go back through history and the literature, virtually every
discovery that's been announced using spectroscopy has been wrong and had
to be retracted because people rushed into things! For example, back in
the Mariner 6 & 7 days the principal investigator who took the spectra of
Mars announced at a press conference a week later, that methane had been
found on Mars. The only thing that produces methane in a planet is life.
Wow! Life on Mars! Well it turned out that a young guy had just published
his Ph.D. dissertation at Caltech, with those exact spectra lines in it,
which the principal investigator thought was methane. It turns out that
the spectra were some previously unknown absorption bands due to carbon
monoxide ice, which is a far less exciting thing to discover. So the
principal investigator got very excited and announced things far too
early, because after all, for discovering life on Mars you go down in
history but for discovering carbon monoxide you don't! But you do go down
in history for a royal blunder and that is hard to recover from.

It's easy to see why people have been discovering the wrong things. Every
substance under the sun, including you and me, has a beautiful
characteristic infrared spectrum because we're all made up of molecules in
crystal structures and cells that vibrate. These vibrations are absolutely
diagnostic of whether you're a mineral, carbon dioxide ice, water ice or
gas. The TES instrument can detect everything because everything has an
infrared spectrum. The bad news is that everything has an infrared
spectrum and when you're trying to look at the minerals on the ground, you
have to look through gases in the atmosphere, dust in the atmosphere, and
water ice and clouds in the atmosphere. This is where you have to be
incredibly careful not to confuse a mineral on the ground that's got an
absorption feature that matches some mineral, but also matches carbon
monoxide in the atmosphere. You have to be very cautious about what you
announce. We're going to try and concentrate on what we hope are very
strong obvious features that we can detect conclusively at first.

Today I'm working on two proposals that are due at the end of August, for
instruments on the 2001 lander and orbiter going to Mars. I really want to
participate in those missions! We've got an excellent team and good ideas
so I'm spending a fair amount of my summer writing proposals for the next
set of missions.
I'm incredibly psyched now. A month ago I was burned out but the
Pathfinder lander has gotten me excited again. My biggest fear all along
was that we'd fly the most spectacular instrument you could imagine to
Mars and every spectrum would look the same--that Mars is made up of one
type of rock, namely basalt, and there are none of these are evaporites
and lake bed or hot spring deposits. But looking at the landscape and
seeing that the rocks in the color pictures look different, has got me
totally pumped!


[Editor's note: This status report was prepared by the Office of the
Flight Operations Manager, Mars Pathfinder Project, NASA Jet Propulsion

July 30, 1997
4:30 p.m. Pacific Daylight Time

Pathfinder's 10.5-kilogram (23-pound) rover called Sojourner stalled today
during the last stretch of its journey to a rock nicknamed Mermaid, but
was quick to recover and prepare for completion of the traverse tomorrow.

Data returned this morning from the Sagan Memorial Station indicated that
the rover's left front wheel stalled during the third of four waypoint
maneuvers. Waypoints are navigational instructions -- consisting of x- and
y-axis coordinates -- used by the rover to travel from one rock to
another. To complete today's traverse to the rock nicknamed Mermaid, for
instance, the rover had to make four short trips based on four sets of
waypoint coordinates. Its wheel jammed during the third segment of the

"This stall was probably caused by a small rock becoming jammed in one of
the rover wheel's cleats," said Flight Director David Gruel. "Once the
rover detected the stall on its own, she was able to autonomously clear
the problem by backing up a short distance. Since the stall did not exist
after the backup was performed, there's a high probability that Sojourner
is ready to continue the drive around the lander tomorrow." Approximately
55 megabits of engineering and science data were returned today. All data
indicated the lander and rover are healthy and the lander's battery
continues to power the craft through the subfreezing nights on Mars. The
rover returned a "spectacular" image today of the rear of the lander and
the rock nicknamed Mini Matterhorn.

Temperatures on Mars today ranged from a balmy minus 13 degrees Celsius (8
degrees Fahrenheit) at 5:35 p.m. local solar time to minus 79 degrees
Celsius (minus 105 degrees Fahrenheit) at 5:30 a.m. local time. Winds were
light and from the west.

On this Martian day, Sol 26, Earthrise occurred at 2:09 a.m. PDT and
sunrise followed at 5:12 a.m. PDT. The Earth later set at 3:43 p.m. PDT
and Pathfinder will observe its 26th sunset at 6 p.m. PDT.

For further information, please visit our website at

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status reports, subscribe to the mfp-status list by sending mail to: In the body type only these words: subscribe


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