Martian soil may contain detrimental substance

NASA's Phoenix spacecraft has detected the presence of a chemically reactive salt in the Martian soil, a finding that if confirmed could make it less friendly to potential life than once believed.

Scientists previously reported that the soil near Mars' north pole was similar to backyard gardens on Earth where plants such as asparagus, green beans and turnips could grow. But preliminary results from a second lab test found perchlorate, a highly oxidizing salt, that would create a harsh environment.

The first test "suggested Earth-like soil. Further analysis has revealed un-Earthlike aspects of the soil chemistry," chief scientist Peter Smith of the University of Arizona in Tucson said in a statement Monday.

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