monster_names.jpg

This image mosaic of the Ares Vallis landing site made from the "monster" pan shows the names of rocks and other features. The names are unofficial. They are used by the Pathfinder team to help keep track of the many features at the site.

MARS PATHFINDER MISSION STATUS
1 October 1997, 4:00 p.m. PDT

The Pathfinder team used today’s passes over the 70 meter deep space network stations in Canberra and Madrid, to attempt to get engineering data from the spacecraft. Although we were not able to obtain engineering data as we had hoped, we did learn another important piece of information that has assisted us in putting more pieces of our puzzle together. By watching the signal from Pathfinder’s auxiliary transmitter were able to see when the spacecraft powered on this morning. The power on was later than expected due to what appears to be extra loads on the spacecraft. We believe that these loads may be the result of some hardware failure, or may have been caused by sequences that run every morning when the spacecraft wakes up.

Normally execution of our morning sequences is not a problem. However, since we believe that the spacecraft battery may no longer be operating ,the spacecraft has lost track of time. This loss of time causes loads to be turned on when there may not be enough power to support them. The initial lack of power is due to the fact that the Sun has not risen high enough to fully illuminate the solar panels and provide the required power. The spacecraft will not power on until it determines that there is enough power to operate its critical systems.

This will cause the spacecraft to wake up later in the morning and power off sooner in the afternoon than we would normally expect. This may explain some of the behavior we have been seen in the last several days. Tomorrow we will once again attempt to receive engineering telemetry data from the spacecraft. We will also be sending commands to put the spacecraft in the safest state possible for the current no battery situation. This will include taking the battery off-line. We expect to receive signals from the auxiliary transmitter indicating the completion of certain events that have been executed to save the spacecraft.

Although the exact causes of our communication problems have not been identified, we do believe that they are related to the degradation of the spacecraft battery. We have over the past two days received good indication that the spacecraft is commandable and able to communicate with us via the auxillary transmitter.

This information means that we can continue to operate the spacecraft. The spacecraft will gradually move towards using the other antennas and transmitters and will verify they are operating correctly.

For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.