Goals

New knowledge from the twin rovers will uniquely contribute to meeting the four overarching goals of the Mars Exploration Program, while complementing data gathered through other Mars missions:

Goal 1:   Determine whether Life ever arose on Mars   [more on Goal  1 for the entire Mars Exploration Program]

Life, as we understand it, requires water, so the history of water on Mars is critical to finding out if the martian environment was ever conducive to life. Although the Mars Exploration Rovers do not have the ability to detect life directly, they will be offering very important information on the habitability of the environment in the planet´s history. The rovers will focus on questions concerning water on Mars: its past, where it was located, and the chemical and geological interactions with the rocks and soil. Close-up studies of surface samples will reveal new details of Mars mineralogy that may help answer whether water was involved in rock and soil formation, and the nature of those processes. This knowledge, in turn, will point the way to areas on Mars that may have been favorable for life in the past.

Goal 2:   Characterize the Climate of Mars    [more on Goal  2 for the entire Mars Exploration Program]

Recorded in the structure and mineral content of Mars' rocks and soils are signs of the environmental conditions under which the materials were formed and altered. Detailed studies of rock samples with the rover instruments will reveal climate details of Mars´ past, which may have been warmer and wetter. In addition, one science instrument will periodically look up to gather temperature profiles of the atmospheric boundary layer - the layer of atmosphere from the surface up to 10 kilometers (6 miles) in altitude. This part of the atmosphere cannot be well observed by orbital instruments, and the data returned will provide important basic information for understanding the current climate on Mars.

Goal 3:   Characterize the Geology of Mars    [more on Goal  3 for the entire Mars Exploration Program]

The rovers are equipped with some of the tools a geologist would carry into the field, as well as the scientific instruments a geologist would use in a lab to study collected samples. Detailed mineralogical study of rock samples will reveal their content and the conditions in which they formed. A tool to scrape away weathered surfaces of rocks will expose fresh surfaces for close-up study.

Of particular interest to the rover science team are minerals containing the element iron, which interacts strongly with liquid water. Did the reddish Martian soil form billions of years ago when the planet may have been wetter and warmer, or is the rusty soil simply the result of ongoing interaction of an oxidizing atmosphere with the surface rocks? Other searches for geological evidence of water will be for clays, carbonates, salts and other minerals that formed in the presence of water.

The local measurements made by the rovers at two landing sites will be used to calibrate similar measurements made from orbit, so that we can extend what we learn to larger regions of Mars.

Goal 4:   Prepare for Human Exploration    [more on Goal  4 for the entire Mars Exploration Program]

The Mars Exploration Rovers will characterize the chemistry and mineralogy of the Martian soil and dust, and perhaps some of the potential hazards that they may pose to humans. Through its studies of surface mineralogy, the mission will help in the assessment of soil and rock as potential in-situ resources for future human missions. The rovers will also contribute to studies of how well the rovers can traverse given characteristics of the soil (for instance, how much resistance the soil provides, how far down the wheels sink etc.). This knowledge will help in planning for other future vehicles that might be needed on Mars.