Washington - After months of dust storms and severe cold, NASA's Phoenix Mars lander was declared dead Monday by mission scientists, who celebrated the probe's success as the first to touch ice on the red planet. Mission managers said that Phoenix had lasted long after its planned 90 days, and they celebrated the success of the spacecraft.
"It's really an Irish wake and not a funeral," said Peter Smith, Phoenix mission principal investigator at the University of Arizona in Tucson, in a teleconference call with reporters.
Barry Goldstein, project manager at the Jet Propulsion Laboratory in Pasadena, California, said the last message from Phoenix had been heard on November 2.
Since then, orbiting communication satellites have picked up no transmissions from the lander.
By late October, it was clear that Phoenix was slowly dying, as NASA shut off one of the craft's heaters in a bid to save energy. Fierce dust storms lasting for days and increasing cold made it "harder and harder for the vehicle to wake up" every morning and use its solar panels, Goldstein said.
Since Phoenix reached Mars on May 26, it uncovered water ice on Mars while examining soil samples but also detected a toxin in the soil that could make the existence of life on the planet less likely.
Phoenix used its weather study equipment to monitor "snow falling and frost on the ground - an all-time first," Smith said.
The snow evaporated before it reached the ground, Phoenix scientists said in September.
Scientists found calcium carbonate - the main component of chalk - and possibly clay, both of which form only in the presence of liquid water.
Phoenix was designed to function for 90 days, but the lander held on for an additional 60 days, making the mission a "huge success," Goldstein said.
Doug McCuiston, director of Mars exploration at NASA headquarters in Washington, said that scientists had learned a lot from the mission about handling soils and "how difficult it is to handle ice."
The next NASA scouting mission to Mars will be Maven, slated for launch in 2013. Maven is to explore Mars' upper atmosphere, McCuiston said.
