Mars lander might have found ice traces

Images from NASA’s Phoenix lander released late Thursday appear to confirm the presence of buried ice on Mars, the first evidence that the spacecraft landed in the right spot last month to find water on the Red Planet.

Pictures taken of a trench dug earlier in the week by the lander’s nearly 8-foot-long robotic arm showed that eight small, whitish chunks of material at the base of the trench had disappeared by Thursday.

If those chunks had been some form of salt, as some scientists believed, they would not have evaporated, said Peter Smith of the University of Arizona, the lead scientist for the $420 million mission.

“It must be ice,” Smith said. “These little clumps completely disappearing over the course of a few days, that is perfect evidence that it’s ice. This has been a wonderful day.”

Phoenix parachuted to the Martian north pole May 25 with the primary goal of finding water, which is crucial for determining whether the planet ever was, or still might be, habitable for rudimentary forms of life.

Water is also a key element of NASA’s long-range dreams to send humans to the planet because it not only would be necessary to sustain the first generation of pioneers but would be a source for fuel.

The orbiting Mars Odyssey spacecraft in 2002 detected large quantities of hydrogen below the surface at the poles, a finding that scientists said indicated vast quantities of ice. But even though the lumpy, fissured landing site on a northern Martian plain reminded some geologists of Earth’s Arctic, the science team could not be sure it had landed in the right place.

Unlike the twin Martian rovers Spirit and Opportunity, Phoenix is incapable of movement, so tension was high among the scientists at the University of Arizona and the Jet Propulsion Laboratory in La Cañada Flintridge, Calif., which is managing the mission for NASA.

Phoenix will not have a long life, so the arrival of the Martian winter in a few months will coat it with carbon dioxide ice, preventing its solar cells from gathering sunlight.

Nearly two weeks ago, the lander’s robotic arm began digging into the soil.