MSNBC - Mystery Martian ‘car wash’ helps rover
MSNBC - Mystery Martian ‘car wash’ helps rover: "A phenomenon akin to a space-borne car wash has boosted the performance of one of the two NASA rovers probing the surface of Mars.
Layers of dust have been swept from the solar panels of the Mars Opportunity vehicle while it was closed down during the Martian night."
Spirit and Opportunity were the first successful probes after the Martians zapped several earlier ones. Now they're obviously feeding Opportunity just exactly what they want us Earthlings to see. (What's the smiley for tongue-in-cheek?)