MARS PATHFINDER MISSION STATUS
9 October 1997, 3:00 p.m. PDT

Today the Mars Pathfinder team attempted to get the spacecraft main transmitter on via ground commands from the Madrid Deep Space Network station. We attempted to do this three times, but was not able to see the signal.

Yesterday, the team spent the day reviewing the predicted thermal state of the spacecraft and the possible operational implications of low temperatures the spacecraft is currently operating at. We did this in order to determine if these low temperatures could be part of the problem we are currently seeing. The current problem seems to be related to sporadic commanding. After analysis of some thermal data, the team decided to modify some of the Deep Space Network operating procedures to try to compensate for possible telecommunications hardware variations due to cold temperatures on the Pathfinder spacecraft. Normally, we don't have this problem because we turn on the spacecraft transmitter for a few hours each day. This warms up the spacecraft significently. However, since we have not been able to do this for the past eleven days, the spacecraft's temperatures are lower than normal.

Today, after our command session, we discovered another telecommunication hardware operating characteristic that is significently different at lower temperatures. We will modify the Deep Space Network's configuration before our command session tomorrow to try to adjust for this.

Tomorrow, we will once again try to turn on the spacecraft's main transmitter. If we are successful, we will set the spacecraft's clock and uplink a sequence that will attempt to send us data the next day over the high-gain antenna. The team is currently still hopeful that this latest configuration change will help us the current commanding problem.

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

.