Posted: Wed, Jan 28, 2009, 8:53 PM ET (0153 GMT)
NASA's Mars rover Spirit, exploring the Red Planet for over five years now, is suffering from "unexpected behavior" in the last few days, NASA announced late Wednesday. On Sunday the rover indicated that it had received instructions to drive to a new location but had not moved; it also failed to record data for the day in non-volatile memory on the spacecraft. To test to see if the rover had lost its orientation, rover controllers sent instructions to Spirit to find the Sun with its camera on Tuesday. Data returned from Spirit indicated that the rover had attempted to carry out the instructions but failed to find the Sun. Project officials said they don't know what the root cause of the problems is, but are looking into a number of possibilities, including the aftermath of a cosmic ray hit on the rover's electronics. The rover, which marked five years on Mars earlier this month, is otherwise in good health.

Related Links:

•  SPACE.com article
•  Computerworld article
•  AP article
•  NASA/JPL press release