Martian Rover 'Spirit'

Loses power to a wheel. 'Spirit' is suffering from low power in general, because Martian winter is approaching and the solar panels are picking up less and less sunlight every day. Rolling into the sunset, bit by bit, but still rolling, and still generating data!

While driving eastward toward the northwestern flank of "McCool Hill," the wheels of NASA's Mars Exploration Rover Spirit churned up the largest amount of bright soil discovered so far in the mission.

... A few days earlier, Spirit's wheels unearthed a small patch of light-toned material informally named "Tyrone." In images from Spirit's panoramic camera, "Tyrone" strongly resembled both "Arad" and "Paso Robles," two patches of light-toned soils discovered earlier in the mission. ... Spirit's instruments confirmed that those soils had a salty chemistry dominated by iron-bearing sulfates. Spirit's miniature thermal emission spectrometer is analyzing this most recent discovery, and researchers will compare it with those other deposits.

These discoveries indicate that light-toned soil deposits might be widely distributed on the flanks and valley floors of the "Columbia Hills" region in Gusev Crater on Mars. The salts may record the past presence of water, as they are easily mobilized and concentrated in liquid solution.

For months, people were quietly heartbroken that 'Spirit' was set amid what appeared to be exclusively volcanic plains. Once in the Columbia Hills, and with these sort of discoveries, 'Spirit' was able to redeem itself, and confirm what people had long suspected, that Gusev Crater had once, many eons ago, seen at least some water.