MARTIAN SOIL GETS BAKED

Abstract

AFTER THREE WEEKS of flexing its mechanical joints on the surface of Mars, the Phoenix lander is doing some science. The soil sample scooped by the probe’s robotic arm has not yet yielded any surprises—it contains carbon dioxide, but no water, for example—but the analyses are just beginning, mission scientists say. The testing finally began after a few tense days during the week of June 8, when engineers worked to coax a clumpy scoop of martian dirt into one of eight ovens on the probe. There, the soil is undergoing cycles of increased heating, and evolved gas will then be analyzed by a mass spectrometer. The goal of the mission is to study the possible ancient role of water near Mars’s north pole, a region where NASA’s Mars Odyssey spacecraft detected fields of subsurface ice several years ago. Images from Phoenix show a stark white substance about 5 cm down in the trenches ...