Sol Highlights:
186 - After a night of deep sleep, Opportunity started the sol with imaging of the sky in search of clouds and using its miniature thermal emission spectrometer for observations of the sky and ground. In the afternoon, the rover took microscopic images of a target called "Tuktoyuktuk," then used its rock abrasion tool to gnaw a hole 7.7 millimeters (0.3 inch) deep into that target. The robotic arm moved the alpha particle X-ray spectrometer into position for reading of the composition of the freshly exposed interior of the rock.
187 - Opportunity woke for an early morning Mars Odyssey communications relay session. After that, the rover started the alpha particle X-ray spectrometer reading, which lasted until 9:00 a.m. local solar time. Opportunity then took a long nap as the uplink command window was delayed until 1:00 p.m. local solar time due to launch of NASAs Messenger mission to Mercury. In the afternoon, Opportunity rotated its tool turret from the alpha particle X-ray spectrometer to the Mössbauer spectrometer and acquired a 7-hour Mössbauer reading before beginning deep sleep.

The rover team is addressing some concerns about rover slippage and about error messages from the microscopic imager. An uphill driving test is planned for sol 188 to gain better understanding of a 40-percent slip observed in a repositioning maneuver on sol 185. This will aid planning for a potential drive clockwise across the inner slope of the crater toward rocks called the "Arctic Islands" and the base of "Burns Cliff." Diagnostic work is also planned for sol 188 about the error messages generated during use of the microscopic imager.