Drama unfolding on Mars

Yesterday, Phoenix (the Mars polar explorer; the machine that found actual water ice on Mars, and that recently detected snow virga falling high above the Martian Arctic plains) fell silent.

The scientists were expecting it to happen sometime around now. As Martian Winter approaches, the sun (already only a fraction as strong as seen from Earth) is sinking lower in the sky, reducing the output of the craft's solar panels. Plus, a wind storm had sprinkled dust on the panels, further reducing their output. Two days ago, during the long, cold Martian night, temperatures dropped to -141F (-96C). The next morning, Phoenix failed to phone home.

To wring every last bit of data from the instruments, mission scientists had built in a "Lazarus Mode" to Phoenix: When things got this dire, it was to go into an ultra-low-power mode where it basically would bide its time and use whatever sunlight is available to try to recharge its drained and ice-cold batteries.

Once a day, for two hours, it would try to wake up, warm up a few essential instruments, take a few quick readings, and weakly squirt the data to the Mars Orbiter passing overhead. The Orbiter would take the faint signal, amplify it, and send it Earthward.

That's the theory. But Phoenix is a one-off, and in a place human instruments have never gone before. Would it work, or was the mission gone?

Yesterday, the safe mode worked and scientists got a brief data squirt from the dying lander high in the Martian Arctic.

But even the low-power mode will only work for a little while. It's only a matter of days, perhaps a few weeks at best, before Phoenix shuts down for good.

Interesting stuff:

http://www.nytimes.com/2008/10/31/science/space/31lander.html

http://phoenix.lpl.arizona.edu/

http://www.google.com/search?q=MARS+PHOENIX+LANDER