The Mars Exploration Rovers' fourth Martian winter is proving to be the harshest one yet and Spirit and Opportunity are getting colder than ever before. With temperatures on the Red Planet dropping in April and the Martian winter solstice still two weeks away, the season has turned into a shivering nail-biter.
Spirit had been communicating on a once-per-week schedule in recent weeks. During the designated time for the rover to communicate with NASA's Mars Odyssey orbiter passing overhead on March 30, Odyssey heard nothing from the rover.
March seems to have come in like a lamb and gone out like a lion on the Red Planet this year as the Mars Exploration Rovers trudged deeper into their fourth winter. While Opportunity finished up work at Concepcin Crater and shifted into gear back on the road to Endeavour Crater, Spirit finished up winter preparations and carried out a limited winter agenda before shifting, it appears, into hibernation mode.
As winter put the freeze on in the southern hemisphere of the Red Planet, the Mars Exploration Rovers slowed down a bit, but continued throughout February to demonstrate the mettle that made them famous: Spirit successfully drove backwards, parked in place for the season, then continued working, as Opportunity roved through rock debris on a cruise around the rim of Concepcin Crater.
I think a goodly proportion of you readers have already figured this out for yourselves since it was launched last March, but I didn't download and install it until last weekend, so this is new to me: Google Mars is awesome.
The Jet Propulsion Laboratory posted a video to YouTube today showing what seems to be a remarkable amount of motion out of Spirit lately, especially given that she's supposed to be a "stationary science platform" now.
Five and a half years after they were supposed to be history, the Mars Exploration Rovers celebrated their sixth Earth year on the Red Planet with Opportunity pulling up to a fresh, new crater on the road to Endeavour, and Spirit working on repositioning itself to settle in for the coming Martian winter, and perhaps the rest of its mission.
There was a press briefing today that announced the official end of efforts to extricate Spirit from her sand trap at Troy. Instead, the rover drivers will now focus on improving the chances that Spirit will survive the coming winter so that she can carry on doing science once the power situation improves in the spring.
The Mars Exploration Rovers quietly wrapped up 2009 this month: Spirit continued to valiantly spin its wheels in an attempt to get out of its embedded location on the west side of Home Plate in Gusev Crater; and Opportunity continued its investigation of Marquette Island, perhaps the oldest Martian rock it's found to date at Meridiani Planum.
I just got a press release from the Jet Propulsion Laboratory that made my heart sink; the extrication effort for Spirit is not going at all well. I did not want to keep sounding a knell of bad news. But once in a while, I do have to report bad news.
I've gotten this question about once a week since Spirit got stuck, but yesterday, two different readers asked the same question within an hour of each other, so I figured it was time for a blog entry.