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Mars Pathfinder Mission Status
July 22, 1997
12 Noon Pacific Daylight Time
Two-and-a-half weeks after landing in an ancient Martian flood basin known as Ares Vallis, Mars Pathfinder has fulfilled all of its primary science goals and continues to operate nearly flawlessly, the flight team reported at today's press briefing.

More than 300 megabits of data have been returned just in the last week, said Dr. Matthew Golombek, Pathfinder project scientist. The rover continues to follow an aggressive series of maneuvers to study rocks and soils identified by the science teams for their interesting features. In addition, the rover's wheel tracks and soil abrasion experiments are beginning to yield new information about the Martian soil, which appears to be finer than talcum powder.

Worldwide interest in the mission has peaked, with more than 400 million hits reported on the Internet today, said Kirk Goodall, Mars Pathfinder web engineer. Goodall and David Dubov, Mars Pathfinder webmaster, constructed 20 Pathfinder mirror sites prior to landing day to service the public. The most hits received in a single day -- 46 million -- occurred on July 8, Goodall said, which is more than double the number of hits received in a single day during the 1996 Olympic Games in Atlanta, Georgia.

A communications problem experienced last weekend has been resolved, reported Richard Cook, Mars Pathfinder mission manager. The problem was associated with ground operations, which has been required to reconfigure equipment and software on a daily basis, and the necessity of establishing communications links only during the short periods of time each day when the lander's transmitter is on.

Scientists are beginning to learn more about the Martian soil by studying the rover's wheel tracks, asking it to perform soil abrasion experiments and measuring the material properties of dust and soil through these wheel-soil interactions. Dr. Henry Moore, a rover scientist with the U.S. Geological Survey in Menlo Park, CA, likened the Martian soil to a very fine-grained silt that could be found in Nebraska. The Martian particles are less than 50 microns in diameter, which is finer than talcum powder.

Dust coverage on some of the spacecraft instruments is accumulating at a very low rate of about a quarter of a percent per day, added Dr. Geoffrey Landis, NASA Lewis Research Center in Cleveland, which is very close to the team's original predictions. These measurements also indicated that the dust was not moving toward the Martian poles right now. Additional study of dust patterns in the Martian environment may shed more light on the ways in which dust leaves the Martian atmosphere.

Dr. Peter Smith, University of Arizona, who is principal investigator of the lander camera, described more about the Martian landscape, pointing out a shallow riverbed crossing through the landing site and rocks in the distance that were washed into this outflow channel from the Martian highlands. About four distinct impressions left by the airbags were evident in the images presented today, noted Dr. Tim Parker, a science team member at JPL. The disturbed soil suggested that the spacecraft was nearly rolling, rather than bouncing, by the time it came to a stop. Parker estimated that the spacecraft bounced 15 to 20 times over a kilometer (6/10ths of a mile) of the landing site before stopping.

Science activities tonight will take the rover through the "cabbage patch," an area of soil in between Scooby Doo and a light-colored rock named Lamb. The rover will conduct a soil experiment , then turn and move toward Lamb. Scientists will take measurements of the dark soil near that rock before moving Sojourner close enough to place its spectrometer against the rock.

On this Martian day, Sol 18, Earth rose over the Sagan Memorial Station at 8:47 p.m. PDT yesterday, July 21. Sunrise was at 11:54 p.m. July 21 and Earth set occurred this morning (July 22) at 10:25 a.m. PDT.

An audio update on Pathfinder's status can be heard by calling 1-800-391-6654.

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