The Phoenix Scout Mission

Phoenix will restore the 2001 lander to flight condition and select a scientic payload from instruments flown on Mars Polar Lander and delivered for the 2001 lander. Landing in May 2008 at the beginning of northern Summer, Phoenix will explore the subsurface ice layers discovered by Odyssey scientists at about 70 N latitude. Descent and panoramic imaging will reveal the small scale geology of this ice-rich region and a robotic arm will dig layer by layer beneath the surface. A German-supplied camera on the arm will examine the trench walls for stratigraphic clues to the origin of the region. Two instruments on the deck will receive samples taken from various depths from the surface to an impermeable ice layer. A thermal evolved gas analyzer (TEGA) will accept samples in one of eight ovens, heating the samples to 1000C will performing differential scanning calorimetry on them. The gases are piped to a mass spectrometer and all species between 1 and 140 Da are identified. Altered minerals (clays, carbonates,etc.) and organics materials can be clearly identified by the multi-dimensional nature (mass, temperature, and depth) of this experiment. Isotopic ratios for hydrogen, neon, argon, carbon, and nitrogen will give clues to the history of the soils and ices. The MECA instrument performs microscopy, electro-chemistry, and conductivity measurments on samples. Bringing water from Earth and mixing it in a sealed cell with samples creates the same conditions as when the ice melts beneath the surface and allows us to determine the acqueous chemistry of the soils. Acidity, redox potential, and salt content are all acquired giving us the first idea of what the biological potential of this habitat might be. Microscopes examine the grain structures and the thermal and electrical conductivity of the soil is examined with a special probe on the scoop. A Canadian MET station uses a lidar to measure the depth of the boundary layer and also pressure and temperature throughout northern Summer and Fall. Phoenix provides insight into the biological potential of the near surface ice.