Team listens for Spirit; Opportunity's power improves with passing of winter solstice

Spirit remains silent at her location called "Troy" on the west side of Home Plate. No communication has been received from the rover since Sol 2210 (March 22, 2010).

It is likely that Spirit has experienced a low-power fault and has turned off all sub-systems, including communication and gone into a deep sleep. While sleeping, the rover will use the available solar array energy to recharge her batteries. The rover electronics module (REM) is expected to get colder than ever before. When the batteries recover to a sufficient state of charge, Spirit will wake up and begin to communicate over X-band and Ultra-High Frequency (UHF).

Although the rover may not wake for some time, the project has been listening every day for any X-band signal from Spirit through the Deep Space Network (DSN) using the radio science receiver (RSR). The Mars Odyssey orbiter is also listening for any scheduled UHF relay passes. If energy levels for the rover are even lower than estimated, there is the additional risk that the rover may trip a mission clock fault. If that happens, the rover would remain asleep until the batteries have recharged sufficiently and there is enough sunlight on the solar arrays to wake the rover. With the passing of the southern winter solstice (on May 13, 2010), solar energy levels and temperatures should begin to improve.

Total odometry is unchanged at 7,730.50 meters (4.80 miles).

 

Opportunity's power improves with passing of winter solstice

With the passing of the winter solstice and improving power, Opportunity continues to drive towards Endeavour crater.

On Sol 2254 (May 27, 2010), the rover drove about 26 meters (85 feet) to the south/south east. Opportunity drove again on Sol 2256 (May 29, 2010), for about 25 meters (82 feet). But on Sol 2257 (May 30, 2010), a fault occurred with the pancam mast assembly (PMA) that supports the science and navigation cameras. The azimuth joint of the PMA did not move when commanded. On Sol 2259 (June 1, 2010), a set of diagnostic tests were run on the PMA azimuth joint, as well as other actuators as a control. The PMA was found to be okay, which does not explain the earlier fault. So the project is continuing the investigation with more diagnostic tests.

As of Sol 2260 (June 2, 2010), solar array energy production was 269 watt-hours, atmospheric opacity (Tau) was 0.465 (Sol 2256) and the solar array dust factor improved to 0.566.

Total odometry is 20,862.01 meters (20.86 kilometers, or 12.96 miles).

 

Source: Jet Propulsion Laboratory
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