Spirit began Sol 99, which ended at 11:55 p.m. PDT on April 13,
2004, by doing a systematic ground survey with the miniature thermal emission spectrometer. After that, the rover completed a six-position brush mosaic on the rock "Route 66" with the rock abrasion tool. Once the brushing was complete, Spirit analyzed the area with the microscopic imager and Moessbauer spectrometer.The afternoon science for the sol included imaging of rocks called "Back Lot" and "Cameo" with the panoramic camera and the miniature thermal emission spectrometer. Spirit took a short nap and woke up for the afternoon Odyssey pass.
During the martian night, Spirit changed from using the Moessbauer spectrometer to using the alpha particle X-ray spectrometer.
Sol 100, which will end at 12:35 a.m. PDT, April 15, 2004, will be a sol full of roving as Spirit continues toward the "Columbia Hills."
OPPORTUNITY UPDATE: Opportunity Wakes with New "Brainpower" - sol 79, Apr 14, 2004
Waking up to the Ramones' "Teenage Lobotomy," Opportunity began operating with new flight software on its 79th sol on Mars, which ended at 12:16 p.m. PDT on April 14.
Yestersol, the rover took daytime readings with its Moessbauer spectrometer on "Jeff's Choice" -- a soil target in the tailings of the trench that the vehicle dug on Sol 73. This sol, the rover performed a free-air integration of its alpha particle X-ray spectrometer. This procedure measures the effect of the Moessbauer's radiation source on the alpha particle X-ray spectrometer's sensor, allowing the science team to subtract out the Moessbauer influence for an accurate calibration.
In the coming sols, Opportunity will examine the trench with its microscopic imager and alpha particle X-ray spectrometer.