Phoenix will land at high northern latitudes to investigate the exciting discovery of near surface ice by the 2001 Mars Odyssey team. This zone is unique on Mars because it presents the possibility of the periodic presence of liquid water as orbital dynamics change the regional climate. A robotic arm will excavate a trench to allow analysis of the geology and chemistry of samples retrieved from the regolith and the icy layer. Climate studies will provide information on the present-day environment, including horizontal and vertical transport of water vapor during polar summer. Past climates will be studied from the chemical and phisical records left in the soil layers. A mass spectrometer will search and identify organics, isotopic ratios, water, and other chemical species.

To maximize science value while minimizing cost and risk, Phoenix will fly the improved 2001 Mars Surveyor Program (M’01) Lander with three delivered M’01 instruments and two build-to-print Mars Polar Lander (MPL) instruments and enhance the science return with a meteorological station. The M’01 Lander is a highly reliable means to soft-land on Mars by virtue of the extensive review during the restructuring of the Mars program in 2000 and the resultant suggested modifications. Inherent in the lander design is the capability for guided entry and hazard avoidance that will both reduce Phoenix risk and benefit future Mars exploration. .

The Goals and Objectives

Phoenix provides a unique opportunity to examine Mars’ newly discovered reservoirs of water ice. The mission is motivated by the goals of (1) studying the history of water in all its phases, and (2) searching for habitable zones. Phoenix will reach the northern plains in June 2008 between latitudes of 65 and 75° N, and will operate for up to 150 sols during northern summer. The key functional requirement of the mission is to deliver samples of surface and subsurface soil and of ice to the Thermal Evolved Gas Analyzer (TEGA) for differential scanning calorimetry and mass spectroscopic analysis; and to the Microscopy, Chemistry, & Conductivity Analyzer (MECA) for microscopic and chemical analyses. Samples will come from a trench up to one meter deep. Imaging systems will document the morphology of the trench walls put in geologic context by descent and panoramic images. A neutron spectrometer will link Phoenix and Odyssey results. Throughout the mission a meteorology instrument suite will monitor polar weather and local water transport.