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Scientists have spotted what they say must be ice in a trench dug by the Phoenix Mars Lander, US media are reporting today.
This would be a hugely significant discovery because traces of water would be indicative of the presence of some form of life, possibly eons ago.
For the last few days, scientists have wondered whether the dice-sized chunks photographed in a shallow trench are ice or salt. When they went back to photograph them again, the chunks had disappeared.
Lead scientist Peter Smith said he is convinced the ice vaporised after it was exposed. Salt would not have done that.
"It must be ice," he said in a NASA Status Report released by the University of Arizona.
Phoenix has been on Mars less than a month, and Smith has been optimistic the spacecraft would find ice ever since orbiting cameras captured evidence of subsurface ice a few years ago.
One of Phoenix's goals is to dig into the polar region of Mars with a nearly 8-foot robotic arm and examine the soil for organic materials and signs that the ice once melted. The arm transfers soil to an onboard oven and wet chemistry lab for analysis.
Earlier this week, Phoenix successfully transferred its first sample to the oven and to an onboard microscope, and those experiments began.
If Phoenix finds signs that Mars once had a habitable environment, future missions could return and search for signs of life.
- NZHERALD STAFF
