News from Mars continues to pour in. The Phoenix Mars Lander team at UA today announced they detected snow falling from clouds about 2.5 miles above the landing site, but vaporizing before it hits ground.
The other news is that the Lander soil experiments found evidence of calcium carbonate and clays that only form in the presence of liquid water on Earth. The implication is that the Phoenix's landing site was once wet.
[right, samples from the "Snow White" trench found to contain carbonates. Credit, NASA/JPL-Caltech/University Arizona/Texas A&M University]