Water on Mars

Mars is a dry, dusty planet today. But scientists believe it was once covered with water. They have found dried-up riverbeds, lake bottoms, and minerals that only form in water. Some water still exists on Mars today, frozen in ice caps at the poles and possibly underground.

Evidence of Ancient Water

Rovers on Mars have found rocks that were shaped by flowing water. They have also found minerals like clay and salt that form when water is present. Photos from orbit show channels that look like dried-up rivers. Scientists think Mars had a thick atmosphere billions of years ago that kept the water liquid.

Water on Mars Today

Mars still has water, but it is mostly frozen. The polar ice caps contain a lot of water ice. There may also be liquid water deep underground. Finding water on Mars is exciting because water is needed for life. If humans ever travel to Mars, they could use this water for drinking, growing food, and making rocket fuel.

Fun Facts

• Mars once had enough water to cover its entire surface in an ocean about 450 feet deep.
• The Curiosity rover found evidence of an ancient lake in Gale Crater that lasted for millions of years.
• Mars has ice caps at both its North and South Poles, just like Earth.

Did You Know?

Scientists think Mars lost most of its water because its atmosphere was stripped away by the solar wind. Without a thick atmosphere, the water evaporated into space.