The potential discovery suggests that Mars once looked very different than it does today and could once have supported life.
Scientists operating Europe’s Mars Express orbiter say they may have detected huge deposits of frozen water beneath the surface of Mars.
The deposits are estimated to be about 3.7 kilometers thick, meaning they could fill Earth’s Red Sea if they melted or cover the entire Mars with a layer of water about two meters deep.
The new findings suggest that Mars once looked very different than it does today, with glaciers, lakes and river channels, according to scientists.
“We saw evidence of glaciers, extinct glaciers that no longer exist, but also some glaciers covered in dust. Most of the water ice we saw on Mars today is found at higher latitudes, where temperatures are colder and so the ice can be stable,” said Colin Wilson, project scientist at ESA.
“It’s a testament to how much water there would have been on Mars in the past to accumulate mounds of water ice several kilometers thick. That’s a large amount of water. So, we’ve seen evidence of a lot of water on the Martian surface in other places, ” Wilson added.
ESA’s Mars Express orbiter first confirmed the presence of ice on the Red Planet in 2004.
He discovered the deposits in 2007, but it wasn’t clear what they were made of: perhaps giant accumulations of dust, volcanic ash or sediment.
In 2015, NASA also said that Mars appears to have salty waterways.
“Today we are revolutionizing our understanding of this planet. Our rovers are finding that there is much more moisture in the air than we ever imagined,” Jim Green, NASA’s director of planetary sciences, said in a news conference.
Now, 15 years later, new data from Mars Express suggests that the deposits are actually layers of dust and ice.
Potential for future manned missions to Mars
The water ice is found at the equator, not the poles, which surprised scientists.
“We don’t expect to see a polar ice cap at the equator,” Wilson said.
“It’s as ridiculous on Mars as it would be on Earth, but that’s what the data tells us, saying it looks like that.”
This has scientists excited about the potential of human exploration missions.
Since Mars is a cold planet, between 20°C and -153°C, according to NASA, finding frozen water at low latitudes instead of in the polar regions would have made human exploration missions easier.
“One of the reasons we were excited to find water ice at low latitudes is that that is where future exploration missions, particularly human exploration missions, will need to land for reasons of orbital mechanics and also energy availability.” , Wilson said.
The dust and ice layers are covered with a protective layer of dust or ash several hundred meters thick.
“However, if it’s 300 meters deep, it’s not very useful for exploration goals. Unfortunately, this probably won’t be the answer to our human exploration needs,” Wilson added.
Europe’s Mars Express probe departed Earth in June 2003 and arrived at Mars in December 2003. It recently marked two decades of study of the Red Planet.
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Video editor • Roselyne Min