Mars Lander Still Phoning Home as Power Dips

NASA's Phoenix Mars Lander is clinging to life and communicating daily with mission controllers though its power supply is quickly diminishing.

Phoenix has communicated with mission scientists everyday since Oct. 30, when the spacecraft suddenly went quiet after a drop in available power sent it into an inactive ?"safe mode."

The spacecraft is now in its sixth month on the Martian surface - double its initial mission - since landing on the red planet's arctic plains on May 25. Phoenix has been scooping up samples of Martian dirt and the rock-hard, subsurface layer of water ice at its landing site and analyzing them for signs of past potential habitability.

Phoenix is nearing the end of its mission as the fraction of the day the sun spends above the horizon shrinks at its arctic landing site. Dust raised by a storm last week, which contributed to Phoenix's shutdown, continues to block some of the little sunlight reaching the spacecraft.

Information received by NASA over the past weekend shows that Phoenix is running out of power each afternoon or evening, but reawakening after its solar arrays catch morning sunlight.

"This is exactly the scenario we expected for the mission's final phase, though the dust storm brought it a couple weeks sooner than we had hoped," said Phoenix Project Manager Barry Goldstein of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "We will be trying to gain some additional science during however many days we have left. Any day could be our last."

Mission engineers at JPL and at Lockheed Martin Space Systems in Denver, Colo., are attempting this week to send commands to be stored in the Phoenix?s flash memory for science activities to be conducted when the lander wakes up each day.

"Weather observations are our top priority now," said Phoenix Principal Investigator Peter Smith. "If there's enough energy, we will try to get readings from the conductivity probe that has been inserted into the soil, and possibly some images to assess frost buildup."

Phoenix finished scooping up dirt and ice samples late last month. The team filled one of the four remaining unfilled ovens on the lander's Thermal and Evolved-Gas Analyzer (TEGA), which bakes the samples and analyzes their composition. Two more ovens were closed without samples for background measurements and one was left unfilled, Smith told SPACE.com in an email.

The team tried to use the lander's robotic arm to push a sample that was stuck into the wet chemistry lab, but it didn't go in, Smith wrote.

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• Special Report: Phoenix Mars Lander
• New Images: Phoenix on Mars!