MARS Scientists argue over whether droplets on Phoenix spacecraft’s leg are liquid

Abstract

What may be liquid water droplets clinging to a leg strut of NASA’s Phoenix Mars Lander has scientists buzzing—and arguing. Last year, Phoenix spent several months digging and analyzing soil on the martian surface. Photos from the spacecraft’s robotic camera show “droplets of liquid salty water” and mud that splashed during touchdown and stayed liquid for many days, says Nilton O. Renno, professor in the atmospheric, oceanic, and space sciences department at the University of Michigan, Ann Arbor. Conditions on Mars make other liquids less likely. Renno is slated to report this hypothesis at the 40th Lunar & Planetary Science Conference in Houston on March 23. A paper on the droplets is under review at Journal of Geophysical Research . “There is lots of evidence that the drops are...liquid,” he says. Perchlorate ions, which Phoenix discovered for the first time in martian soil, make liquid—as opposed to frozen—water, a possibility because they could lower the freezing ...