Science

Ice deposit on Mars holds as much water as Lake Superior, researchers say

An ice deposit with as much frozen water as the volume of Lake Superior has been found hiding below the surface of Mars in a region astronauts may some day call home.

The deposit accounts for just 1% of all known water ice on the red planet

Researchers have found an ice deposit that has a large amount of water in a region where humans could one day land. (NASA/ U.S. Geological Survey)

An ice deposit with as much frozen water as the volume of Lake Superior has been found on Mars in a region astronauts may some day call home.

Using NASA's Mars Reconnaissance Orbiter, scientists performed more than 600 scans of Utopia Planitia, a mid-latitude region on the planet. The scans revealed an ice deposit that ranges in thickness from about 80 metres to 170 metres and is composed of about 50 to 85 per cent water. The rest is likely comprised of dust and rocky material.

"This deposit is probably more accessible than most water ice on Mars, because it is at a relatively low latitude and it lies in a flat, smooth area where landing a spacecraft would be easier than at some of the other areas with buried ice," Jack Holt of the University of Texas, a co-author of the study, said in a statement.

We know early Mars had enough liquid water on the surface for rivers and lakes. Where did it go?-  Leslie Tamppari, Jet Propulsion Laboratory

Recent studies suggest that billions of years ago Mars was home to a large ocean in its northern hemisphere, which may have made it potentially habitable.

The researchers believe the deposit was likely formed as a result of a snowfall that took place during that time. It eventually built up an ice sheet that was mixed with dust. At the current latitude, which spans 39 to 49 degrees, water is unable to exist at the surface, as it will change from a solid to a gas, a process called sublimation.

This vertically exaggerated image illustrates the region on Mars where scientists found as much frozen water as the volume of Lake Superior. (NASA/JPL-Caltech/Univ. of Arizona)

The newly discovered deposit is covered by a layer of dust believed to range in thickness from about one to 10 metres.

The deposit accounts for just one per cent of all known water ice on the red planet, but will help planetary scientists better understand the history of Mars.

"We know early Mars had enough liquid water on the surface for rivers and lakes," said Leslie Tamppari of NASA's Jet Propulsion Laboratory in the statement. "Where did it go? Much of it left the planet from the top of the atmosphere … But there's also a large quantity that is now underground ice, and we want to keep learning more about that."

ABOUT THE AUTHOR

Nicole Mortillaro

Senior Science Reporter

Based in Toronto, Nicole covers all things science for CBC News. As an amateur astronomer, Nicole can be found looking up at the night sky appreciating the marvels of our universe. She is the editor of the Journal of the Royal Astronomical Society of Canada and the author of several books. In 2021, she won the Kavli Science Journalism Award from the American Association for the Advancement of Science for a Quirks and Quarks audio special on the history and future of Black people in science. You can send her story ideas at nicole.mortillaro@cbc.ca.