(dpa) - The Phoenix Mars lander is examining a sample of soil from an "intermediate depth" of the Martian earth to determine if it is different from dirt at the planet's surface and from a lower icy layer, NASA said Friday.
The lander's robotic arm dug up the sample, called Burning Coals, from a trench dubbed Burn Alive 3 and delivered it to one of the craft's many small ovens early Thursday.
Phoenix had earlier confirmed the existence of ice about 4 centimetres below the surface and is now looking at a layer about 1 centimetre above the ice.
The ovens will perform three tests, first heating it to 35 degrees Celsius to look for ice in the sample, then heating it to 125 degrees to dry out the soil, and finally heating it to 1,000 degrees to determine its composition.
"We want to know the structure and composition of the soil at the surface, at the ice and in-between to help answer questions about the movement of water - either as vapor or liquid - between the icy layer and the surface," said scientist Ray Arvidson.
The mission is to last through September.