"There is water ice on Mars within reach of the Mars Phoenix Lander, NASA scientists announced Thursday
Photographic evidence settles the debate over the nature of the white material seen in photographs sent back by the craft. As seen in lower left of this image, chunks of the ice sublimed (changed directly from solid to gas) over the course of four days, after the lander's digging exposed them."
http://blog.wired.com/wiredscience/2008/06/mars-phoenix-tw.html
Official Announcement from NASA
Photographic evidence settles the debate over the nature of the white material seen in photographs sent back by the craft. As seen in lower left of this image, chunks of the ice sublimed (changed directly from solid to gas) over the course of four days, after the lander's digging exposed them."
http://blog.wired.com/wiredscience/2008/06/mars-phoenix-tw.html
Official Announcement from NASA