Opportunity is on the west rim of Endeavour Crater at the 'Spirit of St. Louis' crater near the entrance of 'Marathon Valley.' The rover had been exploring the outcrops inside the Spirit of St. Louis crater.

On Sol 4011 (May 6, 2015), Opportunity drove 25 feet (7.6 meters) to approach the target, named 'Harold M. Bixby.' The drive was preceded with targeted color Panoramic Camera (Pancam) imagery and followed by post-drive Navigation Camera (Navcam) panoramas. On Sol 4013 (May 8, 2015), the rover began the in-situ (contact) investigation of the same target with a Microscopic Imager (MI) mosaic and then the placement of the Alpha Particle X-ray Spectrometer (APXS) for a multi-hour integration. Additional Navcam panoramas were collected on Sol 4014 (May 9, 2015).

On Sol 4016 (May 12, 2015), Opportunity drove again toward some hummocky terrain, driving about 30 feet (9 meters) to the south. This drive too was preceded with targeted color Pancam imagery and followed with post-drive Navcam panoramas.

On the morning of Sol 4017 (May 13, 2015), the rover experienced a vehicle reset during the high-gain antenna (HGA) pass. A bad address was reported with a range outside of any address space used by the rover's avionics. The cause of the reset is not known at this time. The project is in the process of restoring the rover back to master sequence control.

As of Sol 4016 (May 12, 2015), the solar array energy production was 526 watt-hours with an atmospheric opacity (Tau) of 1.146 and a solar array dust factor of 0.734.

Total odometry is 26.28 miles (42.30 kilometers), more than a marathon.