The Thermal and Evolved Gas Analyzer (TEGA) is an instrument designed to study martian soil and ice. It is a major component of the Phoenix Mars Lander mission which will be making the first visit to the high northern latitudes of Mars.
To be launched in August 2007, Phoenix will land at a site located within 30° of the Martian North Pole. This is the equivilant of being within the Arctic Circle on Earth. The soil in this region of Mars has been determined to contain large quanties of water ice.