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PATHFINDER...LOOKING FOR LIFE
SIGNS
By Sean Henahan, Access Excellence LIVE from Mars Pathfinder Mission Control at the Jet Propulsion Lab in Pasadena, California PASADENA, CA (14 July 1997)- Although unexpected computer resets
and human errors continue to frustrate NASA/JPL scientists, both Pathfinder
and Sojourner continue to function and gather information about the surface
of Mars. Current priorities involve fixing the software bug that is causing
Pathfinder to reset its computer; downloading high-resolution color pictures
to be used for a 3-D virtual panorama; and analyzing goofily-named Mars
rocks with the AXP spectrometer.
Caption: Rover Bumps Yogi (click for animation) Information returned by the Pathfinder from the surface of Mars confirms earlier data sent by the two Viking spacecraft more than 20 years ago. However, as it descended through the thin Martian atmosphere, the Pathfinder reported colder temperatures than Viking. Indeed, the upper atmosphere temperature recorded by Pathfinder ding was the coldest temperature ever recorded on Mars, -275 degrees Fahrenheit (-171 degrees Celsius). This is attributed to the fact that the Viking craft landed during the daytime, while Pathfinder landed at night. The first thing Sojourner did was sample some MArs dust. Analyses of this dust show signs of magnetism, an observation that could help explain the role water played in the formation of the red planet. As far as the search for life is concerned, color filters tuned to detect chlorophyll have not revealed any greenery. NASA has also announced that it is creating a virtual reality version of the Pathfinder landing area based on photos sent back by the craft. The virtual Mars environment will be made available to the public on the World Wide Web.  PASADENA, California (9 July 97)- Fresh spectrometry data gathered by the 'brave little toaster' Sojourner appears to provides support for the Martian origins of ALH84002, the meteorite found on Earth with what may be remnants of extraterrestrial bacterial fossils, report NASA scientists. Analysis of the rock currently known as Barnacle Bill indicates similarities
with what scientists have believed were 12 Martian meteorite remnants gathered
on Earth. Among the similarities, the analyses revealed a high content of
quartz, making Martian geology more similar to Earth's than that of the
Moon. Scientists are now awaiting further data gathered from another rock,
the one known as Yogi. Contact with Yogi was delayed when the Pathfinder
team became concerned that Sojourner might end up stuck in a ditch. Pasadena (8 July 1997)- Once upon a time, maybe billions of years ago, there was water on Mars, and lots of it. So say the scientists who are examining the data coming back from Pathfinder and Sojourner. Analyses of pictures sent back from Mars show what appear to be the remnants of a huge flood in a flood plain large enough to contain all the water in the Mediterranean Sea. The preliminary observations indicate that the flood covered an area several hundred miles wide and moved with extreme speed, as fast as one million cubic meters per second. Scientists base these conclusions on the way the boulders appear to be stacked and piled, and by the presence of what appear to be ruts, grooves and piles of sediment. "Could early Mars have been much warmer and wetter? The implications are enormous because liquid water is the key ingredient for life," said Project Scientist Matthew Golombek. Sojourner is making it way across the flood plain. Having made contact with the rock known as Barnacle Bill, the rover will now say hello to another rock called Yogi. NASA scientists are now analyzing data returned from the spectrometer aboard Sojourner. This will provide much more detail on the kind of rocks in Ares Vallis. The current findings bring up quite a few major questions, including:
Future missions conducted in the next eight years will be able to use
the current batch of information to begin a specific search for answers
to these and other questions.
Caption: AE's Sean Henahan at JPL, next to a full-scale model of Pathfinder
Caption: First Photo of Sojourner on Martian soil "Everything is going absolutely perfectly," Project Scientist Matthew Golombek told reporters at NASA's Jet Propulsion Laboratory. "We're just more excited than you can believe. We've never got a measurement from a rock on Mars. This is a great rock." Scientists also breathed a sigh of relief as Sojourner passed its next test, utilizing the alpha proton x-ray spectrometer to analyze a Martian rock sample. As the Earth-bound drivers gain experience driving the Sojourner by remote control, they will venture further afield through the rock-strewn flood plain of Ares Vallis. PASADENA (5 July 1997)- Pathfinder is transmitting color images from the surface of Mars. The first thing scientists noticed was an airbag blocking the rover's ramp. This problem was resolved, but a new one has surfaced, the rover is not responding to remote commands. Engineers are 'confident' the problem can be fixed. PASADENA (4 July 1997)- Right on schedule, 211 days, 10 hours, 9 minutes and 28 seconds after leaving Earth, the Pathfinder spacecraft, first to visit Mars in 21 years, landed in the designated area known as Ares Vallis. Among its objectives will be to look for geology similar to that seen with the controversial Mars meteorite ALH84002, to help determine if there is, or was, life on Mars. The NASA/JPL team have put the 20 years since craft represents the latest approach to unmanned missions. With the world's press gathered, the voice of Mission Control relayed every new development. First the spacecraft shed it jet propulsion system. Approaching the thin Martian atmosphere at 16,600 mph, the Pathfinder slowed and deployed its heat shields, slowing to 1,000 mph on entry. The heat shield did its job and a parachute deployed after which a radar became active to provide altitude information. At an altitude of 50 feet, the parachute is jettisoned and massive airbags deployed. On recahing the surface, the lander bounced several times, possibly as high as a ten story building. Then came a painful minute of silence as NASA waited for a signal. Finally, Mission Control reported "ELM records signal barely visible", an announcement that brought cheers and tears, as the researchers who had worked on the project for at least five years received the first confirmation from the craft that it had survived the descent. The craft then promptly shut itself down to conserve battery power, waiting for the sun to come up and power up the solar cells. Next, the scientists will continue to bite their nails as they wait for more information than the carrier signal sent by the low-gain antenna on a single frequency (color images for example). If all is well, the Pathfinder scientists will use the onboard cameras to check the terrain and then attempt to release ramps for the bread box sized rover craft known as the Sojourner. Sojourner will then collect rock samples and dump them into the spectrometer for analysis. "Starting with the lander camera stereo images, we will use special goggles to view the terrain in three dimensions, and look for safe paths to travel along in order for the rover to reach specific rocks and regions to conduct science and technology experiments," said Brian Cooper, the primary rover driver on the mission. "Once the path is decided , we will drive the rover using a set of software instructions that will be uplinked to the rover each day." Pathfinder landed in an area called Ares Vallis. This area was considered by NASA scientists to be relatively safe landing spot. with a wide variety of rocks washed down into a flood basin. "Ares Vallis is particularly interesting to geologists because it drains a region of ancient , heavily cratered terrain that dates back to early Martian history, similar to the age of the meteorite Alan Hills 84001, which contains scientific evidence suggesting life may have begun on Mars billions of years ago," said Dr. Matthew Golombek, Pathfinder project scientist." By examining rocks in this region, Pathfinder should tell scientists about the early environment on MArs which is important in evaluating the possibility that life could have begun there." Using an alpha proton X-ray spectrometer, Pathfinder will send back critical geological information which might help bolster the case for martian life. However, Pathfinder's instruments and mobile rover are not designed to provide an answer to the question of life on Mars. Rather, they are designed to provide an in-depth portrait of Martian rocks and surface materials over a relatively large landing area. Pathfinder will also provide back-up for the Mars Global Surveyor, another craft arriving to map the planet in September. Another spacecraft is scheduled to arrive on Mars in 2005. That mission will have the capability to land on Mars, collect rock samples, and return them to the waiting scientists.
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PASADENA, CA (12 July 1997)- After
some unexpected bumps, the Sojourner rover managed to get up close and personal
with the rock known as Yogi. However, because of a bit of oversteering
by Mission Control, evaluation of Yogi with the onboard spectrometer will
be delayed. Although the rover is nearly at the end of its planned lifespan,
NASA scientists are encouraged by its performance and expect it to continue
to function for some time.
PASADENA (7 July 1997)- Now that the major technical
glitches have been worked out, NASA/JPL scientists are sounding increasingly
whimsical with reports that Rover is kissing Barnacle Bill, and will soon
set it sights on Yogi, Caspar, Flat-Top and possibly Hippo (nick-names for
specific rocks.) The Sojourner rover has traveled about one foot from the
Pathfinder lander (now renamed in honor of Carl Sagan) and has sampled soil
as well as applied the alpha-proton x-ray spectrometer (APXS) to an interesting
rock known as Barnacle Bill (named because it appears to be covered in barnacles).
NASA geologists have also analyzed photos being sent back from Mars and
believe they have identified characteristic signs of past water activity.
The next step will be to analyze the data from the APXS.
PASADENA (6 July 1997)- As promised,
NASA/JPL engineers were able to solve the earlier problems with the Mars
rover. In essence, they did what millions of personal computer users do
when the screen freezes, rebooted the system. That and some tinkering with
the modem (another frustating practice well-known to many PC users) cleared
the way for lowering the ramps, releasing the rover and steering it on
to Martian soil. It is the soil, along with local rocks, that will form
the basis of Sojourner's assignment list. One rock, dubbed "Barnacle
Bill" is of particular interest to the scientists.
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