The answer on whether there is water on Mars may finally be answered when results from the Phoenix Lander wet laboratory test finally comes out. It will officially reveal if the sublimating material uncovered in the Martian soil really is made of water.
The picture here on the left shows three small chunks (in the triangular shadow) made by the trough, which disappear after a while. It is believed to be dice-sized ice which sublimated in the thin atmosphere. Check the link to view the gif animation.
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