The potential discovery suggests that Mars was once very different from what it looks like today, and could once have harbored life.
AdvertisingScientists piloting Europe's Mars Express orbiter say they may have discovered massive deposits of water ice beneath the Martian surface.
The sediments are estimated to be about 3.7 kilometers thick, meaning they could fill Earth's Red Sea if they melted, or cover all of Mars in water two meters deep.
According to scientists, the new findings suggest that Mars was very different from what it once appeared, with glaciers, lakes and river channels.
„We've seen evidence of glaciers, extinct glaciers, but some glaciers are covered in dust. Most of the water ice we've seen on Mars today is at high latitudes, where temperatures are cooler. The ice is stable,” said Colin Wilson, project scientist at ESA.
„It's evidence of how much water Mars must have had in the past to accumulate ice sheets several kilometers thick. That's a huge amount of water. So we've seen evidence of a lot of water on the surface of Mars, among other places,” Wilson added.
ESA's Mars Express Orbiter first confirmed the presence of ice on the Red Planet in 2004.
It 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 discovered streams of salt flowing on Mars.
„Today, we are revolutionizing our understanding of this planet. Our rovers have discovered that there is more moisture in the air than we thought,” NASA's planetary science director Jim Green said at a press conference.
Now, 15 years later, new data from Mars Express suggests the deposits are actually layers of dust and ice.
The possibility of future manned missions to Mars
The water ice is located at its equator, not at its 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 is on Earth, but the data tells us it looks that way.”
This excited scientists about the potential of human studies.
Because Mars is a cold planet, between 20C and -153C, finding water ice at low latitudes instead of the polar regions would have made human exploration easier, NASA said.
„One of the reasons we were excited about finding water ice at low latitudes is that future missions, especially human missions, may need to land for reasons of orbital dynamics and power availability,” Wilson said.
Layers of dust and ice are topped by a protective layer of dust or ash several hundreds of meters thick.
„However, if it's 300 meters down, it won't be very helpful for exploration purposes. Unfortunately, it won't replace our human exploration needs,” Wilson added.
AdvertisingEuropa's Mars Express spacecraft left Earth in June 2003 and arrived at Mars in December 2003. It recently spent two decades studying the Red Planet.
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