Scientists on Wednesday told the long-armed spacecraft to dig up three scoops of soil. Over the next several days, it will dump a soil sample into a tiny oven where it will be baked and studied.
Phoenix landed in the Martian arctic plains about 10 days ago on a three-month mission. The robot will study whether the polar environment is capable of supporting primitive life forms.
The mission is led by the University of Arizona in Tucson and managed by NASA's Jet Propulsion Laboratory.