NASA's Spirit rover did not go to sleep today even after ground controllers sent commands twice for it to do so.
Shortly before noon, controllers were surprised to receive a relay of data from Spirit via the Mars Odyssey orbiter. Spirit sent 73 megabits at a rate of 128 kilobits per second. The transmission included power subsystem engineering data, no science data, and several frames of "fill data." Fill data are sets of intentionally random numbers that do not provide information.
Spirit had not communicated successfully through Odyssey since the rover's communications difficulties began on Wednesday.
Spirit's twin, Opportunity, will reach Mars at 05:05 Universal Time on Jan. 25 (12:05 a.m. Sunday EST or 9:05 p.m. Saturday PST) at a landing site on the opposite side of the planet from Spirit.
Source:
http://www.jpl.nasa.gov/index.html