Phoenix Mars Lander May Have Uncovered Ice — which is, of course, solid water:
The Robotic Arm Camera on NASA’s Phoenix Mars Lander captured this image underneath the lander on the fifth Martian day, or sol, of the mission. Descent thrusters on the bottom of the lander are visible at the top of the image.This view from the north side of the lander toward the southern leg shows smooth surfaces cleared from overlying soil by the rocket exhaust during landing. One exposed edge of the underlying material was seen in Sol 4 images, but the newer image reveals a greater extent of it. The abundance of excavated smooth and level surfaces adds evidence to a hypothesis that the underlying material is an ice table covered by a thin blanket of soil.
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“This suggests we have an ice table under a thin layer of loose soil,” said the lead scientist for the Robotic Arm Camera, Horst Uwe Keller of Max Planck Institute for Solar System Research, Katlenburg- Lindau, Germany.“We were expecting to find ice within two to six inches of the surface,” said Peter Smith of the University of Arizona, Tucson, principal investigator for Phoenix. “The thrusters have excavated two to six inches and, sure enough, we see something that looks like ice. It’s not impossible that it’s something else, but our leading interpretation is ice.”