by NASA

“ Phoenix is in development for launch in August 2007. It would land in May 2008 on arctic ground where a mission currently in orbit, Mars Odyssey, has
detected high concentrations of ice just beneath the top layer of soil.
A stereo color camera and a weather station would study the surrounding environment while the other instruments check excavated soil samples for water, organic chemicals and conditions that could indicate whether the site was ever hospitable to life. Microscopes would reveal features as small as one one-thousandth the width of a human hair. ”

“ Did a retreating ice sheet leave it behind? Information such as the amount of layering, the textures of the ice and soil, and the chemical composition at different depths could distinguish among those and other possibilities. ”