Phoenix Mars Lander Gets Last Chance to Rise From the Dead

NASA has given its long-silent Phoenix Mars Lander one lastchance to rise again this week, and has ordered a workhorse orbiter around the redplanet to listen for any beeps of life from the arctic Martian probe.

From May 17 to 21, Odyssey will listenfor a signal from Phoenix during 61 flights over the lander's site in thefar-northern region of the red planet.

So far, the orbiter detected no transmissions from the landerin previous campaigns that totaled 150 overflights in January, February andApril. [DeadMars missions.]

This will be Phoenix's last chance to speak up. Afterwards,it will be relegated to the Marsspacecraft graveyard.

"To be thorough, we decided to conduct this finalsession around the time of the summer solstice, during the best thermal andpower conditions for Phoenix," said Chad Edwards, chief telecommunicationsengineer for the Mars Exploration Program at NASA's Jet Propulsion Laboratory(JPL) in Pasadena, Calif., in a statement.

Phoenix landedon Mars on May 25, 2008, and operated successfully in the Martian arcticfor approximately two months longer than its original planned three-monthmission, which confirmed the presence of water ice beneath the planet'ssurface. Over five months, the lander also studied the Martian soil andatmosphere.

Once winterset in and temperatures dropped, the spacecraft lacked sufficient power tocontinue functioning. The $475 million solar-powered robot was not designed towithstand the dark and cold conditions of a Martian arctic winter.

Phoenixwent silent in November 2008.

In case thelander did survive, however, NASA has used Odyssey to listen for signals thatPhoenix would transmit if abundant sunshine revived the resilient lander.

NorthernMars experienced its maximum-sunshine day, the summer solstice, on May 12 (EasternTime; May 13, Universal Time). The sun will be higher in the sky above Phoenixduring this fourth listening campaign than during any of Odyssey's prioroverflights.

Still, theprobability of hearing from the lander remains low, mission managers have said.

The Phoenixmission is led by Peter Smith of the University of Arizona, Tuscon, withproject management at JPL and development partnership with Lockheed MartinSpace Systems. JPL, a division of the California Institute of Technology inPasadena, Calif., also manages the Odyssey project in partnership with LockheedMartin.

• Gallery- Mars: A Spacecraft Graveyard
• Phoenixon Mars
• SpecialReport: Highlights of the Phoenix Mars Lander Mission