Huge lake discovered on Mars

19-km-wide, beneath ice cap

Using a satellite to peer beneath layers of dust and ice at Mars’ south pole, scientists have detected a 19-km-wide span of briny water, a large, stable reservoir akin to lakes buried beneath the Antarctic ice sheet on Earth.

The long-sought discovery, the largest detection of liquid water on the Red Planet yet, raises the tantalizing possibility of a very cold, very salty niche where life might have once existed — or even persisted.

“This could be, perhaps, the first habitat we find on Mars,” said planetary scientist Roberto Orosei of the National Institute of Astrophysics in Italy, who led the study published in the journal Science.

To be clear, there’s no sign of any actual Martian microbes swimming around, and the environment is not obviously hospitable.

The water at the base of the polar cap is estimated to be of a temperature about minus90F, far below the typical freezing point of water.

Scientists believe the water is kept in liquid form by a salty brine that Orosei and colleagues speculatively describe as a “sludge.”

Scientists aren’t even exactly sure what to call the body of water, which they detected by analyzing radar echoes gathered over three years by the orbiting Mars

Express spacecraft.

They cannot see the bottom with existing equipment, but they estimate it is at least three feet deep, otherwise they would not have detected it at all.

It could be a sub-glacial lake, an aquifer, or a layer of sediment saturated with water. Evidence of water has been seen on Mars many times, but it is usually ancient, fleeting or frozen.

The detection of a long-standing reservoir of liquid water is thrilling evidence that there could be water at the base of Mars’ ice caps, similar to what’s present on Earth.