Winter Wonderland

Winter Wonderland: Opportunity, the Mars Exploration Rover entering its ninth year operating on the Red Planet, has returned this view from its winter resting place on the rim of Endeavour Crater.

Part of a larger 360-degree panorama still being collected, this composite of smaller images looks north toward the stretch of Endeavour's rim known as Cape York, which forms an arc across the top half of the view. Rippled sand and wind-sculpted formations are visible inside the crater.

Opportunity was parked at the site -- dubbed Greeley Haven by the rover team after the late Arizona State university planetary geologist Ronald Greeley -- to ride out the Martian winter. Controllers want to be sure enough sunlight hits the dusty solar arrays seen in the image below to survive the season, which will continue beyond the March 30 southern-hemisphere winter solstice.

In the past Opportunity has been cleaner, but this time operators parked it on the northern-facing slope for maximum exposure to the Sun.

On the other side of the planet, hope is gone for Opportunity's twin rover Spirit. Silent since March 22, 2010, and stuck in deep sand, Spirit is dead for good. The last command was sent to it on March 25, 2011, and controllers stopped listening for a replay last June. This is one of the last images it sent back, on Feb. 13, 2010.

At launch, mission managers were planning nominal three-month missions, with 1 km. of mobility, for each rover. Spirit lasted more than six years, and drove 7.7 km. before it died. Opportunity has traveled more than 34 km. since it landed.

The Mars Science Laboratory, a nuclear-powered rover the size of a Volkswagen bug, should be capable of lasting much longer as it explores the sedimentary layers of the mountain inside Gale Crater. Of course, it must survive its untested "sky crane" landing first.

After that, it may be a while before NASA sends another lander to Mars. Early word on the agency budget request coming up Feb. 13 is bleak on the prospects of any U.S. Mars missions beyond the Mars Atmosphere and Volatile Evolution (Maven) orbiter, with or without international cooperation.

Maven is set for launch in the planetary window that opens late next year. The orbiter will study the planet's atmosphere, gaining valuable new information about the habitability and history of Mars.

But it won't get up close and personal like the rovers.

Images: NASA/JPL-Caltech/Cornell/Arizona State Univ.