Posted on behalf of Amber Dance

The Phoenix spacecraft, having collected evidence for water and ice on the Red Planet, is going for broke. NASA extended its mission today, allowing it to keep up its experiments until the diminishing sunlight, as Mars heads into winter, doesn’t provide enough power and renders it a mere weather station. But unlike the mythical bird, Phoenix is unlikely to rise again when winter’s over.

“The little lander is terminal,” said Doug McCuistion, director of the Mars Exploration Program. “It’s battling the weather and it’s battling the temperatures.” Currently, Phoenix basks in more than 20 hours of sunlight per Martian day, or sol. But that time is decreasing, which means that the lander can collect less solar energy. Simultaneously, the temperature is dropping, so Phoenix must expend more energy to keep its electronics warm. Eventually, the lander will lack the energy to keep going, and although it’s possible it will come back to life when the sun returns, engineers are not optimistic. It is expected to last until November or December. “We’re trying to literally make hay as the sun shines,” McCuistion said.

But for now, Phoenix is doing great, waking up every morning and communing with the orbiter Odyssey. It has been scratching the surface, baking soil samples, and even peering under a rock since landing on 25 May, and has already lasted a month longer than planned. It still has four of its eight ovens, and one of the wet chemistry beakers, left to use.

So far, Phoenix has provided data that makes the Red Planet’s northern plain sound like a winter wonderland. Phoenix observed sublimating ice crystals within a month of landing (Nature). NASA announced today that snow falls from the sky, although it’s not yet clear if flakes reach the surface. And ice lurks just below the surface. “If you were to sweep away the thin soil layer on this flat plain, you would find that it’s more like a skating rink,” said Peter Smith, Phoenix principal investigator from the University of Arizona.

While soil at the landing site is quite dry, it has provided ample evidence for a watery past. Vapors rising from samples in the ovens included water vapor and carbon dioxide. The former probably came from a clay-like material, NASA said. The latter is usually released by carbonates, and the temperature at which the gas was released suggests calcium carbonate — common on Earth as limestone or chalk. Calcium carbonate is formed when gaseous carbon dioxide meets liquid water [Eds – with a bit of calcium around, too], suggesting that at some point in Mars’ past, water flowed.

Before meeting its dark, cold end, Phoenix will look for organic matter and investigate the isotopes in the water it has found. Its Earth-bound controllers will also attempt to activate a microphone on the lander, and perhaps listen to Mars.

Image: NASA