London, June 7 : NASA's Phoenix Mars Lander, which touched down on the surface of the Red Planet on May 26, has begin testing Martian soil for traces of water.
After two test scoops at a site nicknamed 'Dodo,' the spacecraft successfully grabbed its first real shovelful of Martian soil on June 6.
The new sample, pulled from a neighbouring patch of ground dubbed 'Baby Bear', shows signs of a mysterious white substance - thought to be ice or salt - that had been seen in the practice digs.
The lander's arm is now poised above the Thermal and Evolved-Gas Analyzer (TEGA) compartments, which will heat up the soil and test the resulting vapours for water and other components.
"This is really an important occasion for us, to be poised to make a measurement for the first time of the polar soils that'll tell us how much water is in the soil," chief scientist Peter Smith of the University of Arizona in Tucson, US.
TEGA will also test for organic molecules, as well as minerals that might have been shaped by water.
Because TEGA has only eight ovens for analysis, each of which can be used only one time, arm operators wanted to make sure they got just the right amount of soil - enough to guarantee some would fall into the pencil lead-sized opening to the oven, but not so much as to accidentally drop some onto other parts of the instrument.
"We're ecstatic that we got a third to a quarter of a scoopful, roughly the size of a cup. We couldn't be more happy," said robotic arm flight software lead Matt Robinson of the Jet Propulsion Laboratory in Pasadena, California, US.
According to Smith, the first results from the TEGA tests will come in over the coming week.
Phoenix will also deliver another sample to the lander's optical microscope as well as to the wet chemistry lab, which can test for components like salt.
The team may also return the robotic arm to Dodo, where the arm will dig down farther to look for a layer of ice in the soil.