spacetoday.net: Phoenix lander detects Martian snow

Posted: Tue, Sep 30, 2008, 7:07 AM ET (1107 GMT)
Phoenix Mars lander illustration (Univ. of Arizona)

NASA's Phoenix Mars Lander has detected snow falling in the Martian atmosphere and is also finding new evidence of past liquid water on the planet, scientists said Monday. A laser instrument on the spacecraft detected the snow in clouds about four kilometers above the lander. The snow is currently vaporizing before reaching the ground although scientists suggested that the snow could eventually reach the ground as winter approached. Other instruments on the spacecraft have found traces of calcium carbonate and particles that could be clay; both substances form only in the presence of liquid water. The lander, designed to operate for three months, is now entering its fifth month on the Martian surface but is suffering from decreased power as the amount of sunlight available each day decreases in the polar regions. Project officials plan to operate the spacecraft as long as possible, although they said there will not be enough power to use the lander's robotic arm by the end of October.