NASA: Mars rover back on its feet; probe continues

Computerworld - While NASA engineers still don't know what caused problems on board one of its Mars rovers early this week, they say the robotic explorer is healthy and responding to commands again.

More tests are being run today to try to get to the bottom of the glitch that left the robotic machine unresponsive.

The space agency reported earlier this week that its scientists were putting together a series of diagnostic tests to help them figure out why one of the two Mars rovers began failing to respond to instructions.

The Mars rover Spirit started acting erratically over the weekend. Spirit and its Mars rover companion, Opportunity, have been working on the red planet for five years despite initially being given an on-planet life span of three months.

NASA said that on Sunday, Spirit sent information back to Earth indicating that it had received its driving commands for the day, but it did not move. And on the same day, the rover failed to record its activities, as it normally does, into its own memory.

Then on Monday, the rover's controllers sent the robotic machine instructions to find the sun with its camera, in the hopes that that would enable Spirit to reorient itself. NASA initially said Spirit could not find the sun, but later clarified that the rover reported back that it had found the sun but not in its expected location.

NASA said Thursday night that engineers had run diagnostic tests on Spirit during the day, narrowing the number of possibilities of what may have caused the glitch.

"No clear explanation has been established yet," NASA reported online. "Spirit is healthy and responding to commands. It recorded and returned images of nearby scientific targets. Spirit may resume driving over the weekend."

The new tests being run on the rover today include diagnostics for its inertial measurement unit, which is a gyroscope/accelerometer device that measures the machine's movements and "attitude."

The two rovers are among the best pieces of technology that the Jet Propulsion Laboratory has ever built, said Bruce Banerdt, project scientist for the Mars Exploration Rovers, in a previous interview.

The rovers, which are working on the Mars equator but on different sides of the planet, had their five-year anniversary on Mars this month. The machines have been sending and receiving information from Earth every day, with a team of about two dozen programmers and engineers uploading code to guide the rovers' movements and aim their cameras. All of that information travels about 200 million miles one way, taking anywhere from five to 21 minutes to travel from one planet to the other.

NASA scientists have been working to launch an SUV-size rover to Mars next year. However, the space agency announced just last month that testing and hardware problems are pushing back the launch of NASA's $2.3 billion Mars Science Laboratory from next fall to 2011. NASA has been putting a lot of focus on Mars.

Read more about App Development in Computerworld's App Development Topic Center.