NASA has given its long-silent Phoenix Mars Lander one last chance to rise again this week, and has ordered a workhorse orbiter around the Red Planet to listen for any beeps of life from the arctic Martian probe.
From May 17 to 21, Odyssey will listen for a signal from Phoenix during 61 flights over the lander's site in the far-northern region of the red planet.
So far, the orbiter detected no transmissions from the lander in previous campaigns that totaled 150 overflights in January, February and April. (Dead Mars missions.)
This will be Phoenix's last chance to speak up. Afterwards, it will be relegated to the Mars spacecraft graveyard.
"To be thorough, we decided to conduct this final session around the time of the summer solstice, during the best thermal and power conditions for Phoenix," said Chad Edwards, chief telecommunications engineer for the Mars Exploration Program at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., in a statement.
Phoenix landed on Mars on May 25, 2008, and operated successfully in the Martian arctic for approximately two months longer than its original planned three-month mission, which confirmed the presence of water ice beneath the planet's surface. Over five months, the lander also studied the Martian soil and atmosphere.
Once winter set in and temperatures dropped, the spacecraft lacked sufficient power to continue functioning. The $475 million solar-powered robot was not designed to withstand the dark and cold conditions of a Martian arctic winter.
Phoenix went silent in November 2008.
In case the lander did survive, however, NASA has used Odyssey to listen for signals that Phoenix would transmit if abundant sunshine revived the resilient lander.
Northern Mars experienced its maximum-sunshine day, the summer solstice, on May 12 (Eastern Time; May 13, Universal Time). The sun will be higher in the sky above Phoenix during this fourth listening campaign than during any of Odyssey's prior overflights.
Still, the probability of hearing from the lander remains low, mission managers have said.
The Phoenix mission is led by Peter Smith of the University of Arizona, Tuscon, with project management at JPL and development partnership with Lockheed Martin Space Systems.
JPL, a division of the California Institute of Technology in Pasadena, Calif., also manages the Odyssey project in partnership with Lockheed Martin.