PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
Mars Pathfinder Mission Status
October 1, 1997
After experiencing difficulties in communicating with the
Mars Pathfinder spacecraft for the past three days, the
operations team was able to reestablish a brief two-way
communications session Tuesday using the lander's auxiliary
transmitter. Receipt of this beacon signal indicated that the
spacecraft is still operational.
The team began having communications problems with the
spacecraft on Saturday, Sept. 27. These problems could be
related to degradation of the spacecraft's battery. The last
successful data transmission cycle from Pathfinder was completed
at 3:23 a.m. Pacific Daylight Time on Sept. 27, which was Sol 83
of the mission.
No signal was received from the spacecraft on the next
Martian day, Sol 84, which began in the evening of Sept. 27. The
team's transmission session began at 11:15 p.m. PDT. The lack of
a signal, at that time, was thought to be caused by a possible
computer reset incident, ground system problem or low voltage
condition. A reset or a low voltage condition, caused by the
aging of the battery, would cause the spacecraft sequence to
automatically stop and not execute its planned communication with
The team attempted to communicate with the spacecraft again
on Sept. 29 (Sol 85) and Sept. 30 (Sol 86) with no success.
Tonight, on Sol 88 of the mission, the team will use the
auxiliary transmitter again to attempt to acquire engineering
data that will help them assess the cause of the communications
problem. Meanwhile, the rover, which receives its instructions
from Earth via the lander, is currently running a contingency
program which has instructed it to stand still rather than begin
its trek around the lander.
The team will repeat these activities on subsequent days and
attempt to receive telemetry that will give them more information
about the health of the lander and rover.
If Pathfinder operations do not return to normal tonight, a
Mars Pathfinder team representative will provide an update on the
situation at the beginning of the planned Mars Global Surveyor
science news briefing at 9 a.m. PDT on Thursday, Oct. 2.