PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
http://www. jpl.nasa.gov

Mars Pathfinder Mission Status
August 3, 1997
7 p.m. Pacific Daylight Time
      Although the reason for yesterday's loss of downlink opportunities has not yet been identified, science activities proceeded normally today on the surface of Mars. Today, Sol 30, marks the end of the Mars Pathfinder primary mission, 30 days after the spacecraft landed in an ancient outflow channel called Ares Vallis.

      The Imager for Mars Pathfinder (IMP) continued to image the thin Martian atmosphere, the lander's wind socks, the Sun and the rover as it roamed to another destination, said Carl Steiner, Mars Pathfinder flight director. Acting as a weather station, the Pathfinder lander -- now called the Sagan Memorial Station -- gathered weather data for the 12th consecutive day. Data from yesterday's surface operations had been stored onboard the lander and were downlinked today. Highs on Mars rose to minus 10 degrees Celsius (14 degrees Fahrenheit) today and dipped to minus 70 degrees Celsius (minus 94 degrees Fahrenheit).

      The rover finished its soil analysis of Mermaid Dune before heading toward the Rock Garden. An onboard tilt protection circuit caused the rover to shut down after reaching 10 centimeters (0.3 feet) of motion.

      "An especially noisy accelerometer had caused this problem in past, but had successfully guarded the rover against excessive tilt," Steiner said. "The rover team thought it prudent to activate this device, even with the possibility of inadvertent shut-down, because of the uneven path to the Rock Garden and the long traverse." Sojourner will resume this traverse on Sol 32, as Pathfinder's extended mission gets under way.

      Three downlink sessions were successfully carried out today using the low-gain antenna once and the high-gain antenna for the next two sessions, Steiner said. The operations team, however, was unable to complete its planned downlink of an eighth (octant) of the so-called "super pan" before the end of the day and the beginning of a two-day sleep period for the lander.

      "This will be the first time in nearly 240 days that the lander's electronics will be powered off," Steiner said. "At the conclusion of today's activities, all lander electronics, with the exception of a few computer chips that comprise the hybernate circuit, will be powered off to conserve energy through the Martian evening and prolong our waning battery."

      The hybernate circuit has been programmed to wake up the lander at 7:30 a.m. local solar time tomorrow. A backup circuit will wake the lander at 8 a.m. if the lander is still asleep. Tomorrow's activities will focus on recharging the battery to the fullest capacity possible. No science experiments are planned.

      On this Martian day, Sol 30, Earthrise occurred at 4:49 a.m. PDT and sunrise occurred at 7:51 a.m. PDT. The Earth set over the landing site at 6:22 p.m. PDT and the sun set at 8:39 p.m. PDT.

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