London, June 3 : NASA's Phoenix Mars lander, which touched down on the surface of the Red Planet on May 26, has returned back images of Martian soil that might possibly contain water ice.
According to a report in New Scientist, Phoenix's first scoop of Martian soil contains white streaks that could be water ice.
The 420-million dollar spacecraft gouged out its first scoopful of Martian dirt from an area informally known as the Knave of Hearts, using its 2.3-metre robotic arm.
"The material is crushable," said Ray Arvidson of Washington University in St. Louis, Missouri, US, co-investigator for Phoenix's robotic arm. "It's sand with a fair amount of soil and dust," he added.
The practice scoop was emptied onto a designated dump area nearby, but not before a camera snapped images revealing mysterious white streaks in the reddish dirt.
The bright streaks appear in both the excavated soil and in the hole from which it came.
"That bright material might be ice or salt," said Arvidson. "We're eager to do testing of the next three surface samples (to be) collected nearby to learn more about it," he added.
If the streaks are ice, it would be consistent with Martian climate models and measurements gathered by NASA's Mars Odyssey spacecraft, which suggest the Martian poles harbour hard ice beneath thin layers of topsoil, according to Arvidson.
Another hint of possible ice appears in an image beamed back on Friday.
Taken by the wrist-mounted camera on the robotic arm, it shows a bright, flat patch beneath the lander that could be exposed ice.
According to Peter Smith of the University of Arizona in Tucson, US, Phoenix's chief scientist, "We were expecting to find ice within two to six inches of the surface. The thrusters have excavated two to six inches and, sure enough, we see something that looks like ice."
"It's not impossible that it's something else, but our leading interpretation is ice," he added.
This patch could also be a salt deposit, according to mission scientists.