Opportunity is on the west rim of Endeavour Crater heading towards 'Marathon Valley,' a putative location for abundant clay minerals.

The rover's Flash file system was successfully reformatted on Sol 3773 (Sept. 4, 2014).

The Flash space available is slightly smaller (less than 1%) than before the reformat, consistent with the reformatting process flagging some bad cells to avoid. On Sol 3775 (Sept. 6, 2014), some scripts and configuration files were copied back to Flash from EEPROM (other non-volatile storage) were they were kept during the reformat.

Other configuration files were loaded from the ground on Sol 3776 (Sept. 7, 2014). The rover has performed without any anomalies or unusual behavior since the reformat.

A drive was sequenced on Sol 3778 (Sept. 9, 2014), using visual odometry to navigate around potential rock obstacles.

The drive stopped almost as soon as it started because the rover's visual odometry could not find enough visual features for the algorithm to converge. The plan ahead is to re-sequence the drive but to instruct the rover to use a different scene with more visual features for the visual odometry.

As of Sol 3778 (Sept. 9, 2014), the solar array energy production was 694 watt-hours with an atmospheric opacity (Tau) of 0.879 and a solar array dust factor of 0.754.

Total odometry is 25.28 miles (40.69 kilometers).