A probe of the European Space Agency (ESA from the European Space Agency) found enough water to cover Mars in an ocean between 1,5 and 2,7 meters deep, buried as ice beneath the planet's equator.
The find was made by ESA's Mars Express mission, an old spacecraft that has been engaged in scientific operations around Mars for 20 years.
While not the first time evidence of ice has been found near the Red Planet's equator, this new discovery is by far the largest amount of water ice detected there so far and appears to match previous discoveries of water ice on Mars.
"Excitingly, the radar signals match what we expect to see from layered ice and are similar to the signals we see from the polar 'caps' of Mars, which we know are very ice-rich," said the lead researcher. Thomas Watters of the Smithsonian Institution in the United States in an ESA statement.
The deposits are thick, extending 3,7 kilometers underground, and covered by a crust of hardened ash and dry dust hundreds of meters thick.
The ice is not clean, because it is very polluted by dust. While its presence near the equator makes it a more easily accessible location for future manned missions, being buried so deep means that accessing the ice can be difficult.
