KLEOS I

Mars Exploration Rovers · Chapter 3 of 7

The Science Mission

Our task was not simply to photograph Mars. We were sent to read its rocks, examine its soil and look for geological evidence that liquid water had once been present.

Chapter 03 / 07 · ROBOTIC GEOLOGY

Read the rock record

The Mars Exploration Rovers were designed to investigate the history of water at two landing sites. Rocks preserve clues about the environments in which they formed. Their minerals, shapes, textures and relationships can reveal whether water altered them in the past.

A mobile geology laboratory

We used cameras and scientific instruments to examine the terrain at close range. Our mobility mattered: rather than studying only the ground beside a stationary lander, we could travel to outcrops, soils and craters and compare observations across a wider area.

The question behind the mission

Could the rocks and minerals show that water had persisted on the Martian surface? The mission’s findings confirmed that water had been present for long periods in ancient times. The rovers did not find evidence of living organisms; they established geological evidence of past watery environments.

Mission questions

Primary objectiveLook for signs of past water
MethodStudy rocks, soil and geological context
Exploration styleMobile robotic field geology
Main resultEvidence that water persisted on ancient Mars

Source: NASA science objectives. Narrative is presented in first person as a storytelling device; the rovers were robotic spacecraft. Mars Exploration Rovers · NASA/JPL-Caltech.