Looking for Signs of Past Water on Mars

The big science question for the Mars Exploration Rovers is how past water activity on Mars has influenced the red planet's environment over time. While there is no liquid water on the surface of Mars today, the record of past water activity on Mars can be found in the rocks, minerals, and geologic landforms, particularly in those that can only form in the presence of water. That's why the rovers are specially equipped with tools to study a diverse collection of rocks and soils that may hold clues to past water activity on Mars.

Four Science Goals for Mars Exploration

The rovers offer unique contributions in pursuit of the overall Mars science strategy to "Follow the Water." Understanding the history of water on Mars is important to meeting the four science goals of NASA's long-term Mars Exploration Program:


Learn about the rovers' unique contributions
to these science goals through the pursuit of seven
primary science objectives ››

How scientists will rely on the rovers to look for signs of past water

Because scientists cannot go to Mars themselves at this point in time, they have to rely on robot geologists -- the rovers -- to look for signs of past water activity on Mars for them.

To do their job, the rovers carry a number of science instruments that will analyze rocks and soils on the Martian surface and perform other important tasks and studies.

picture of several scientists in a control room