What appears to be an underground lake on Mars has been found, thanks to an ice-penetrating radar from the European Space Agency’s Mars Express orbiter, according to Science News.
The lake was discovered on the planet’s south pole, where NASA’s Mars Reconnaissance Orbiter also searched for liquid water, coming up with nothing.
“It’s a big mystery, we’d love to figure it out,” planetary scientist, Isaac Smith, from the Planetary Science Institute said.
The discovery was announced months ago, but scientists are still unclear about how the lake could be undetectable to NASA’s orbiter.
Planetary scientist, Roberto Orosei, from the National Institute for Astrophysics in Bologna, Italy, said the main issue has been figuring out how the water could remain liquid at an icy depth of -68 degrees Celsius – with even salts dissolved in water being unable to melt ice at that temperature.
After researching the situation further Orosei said that if the south polar ice cap on Mars has a texture similar to styrofoam, which is porous, it could both insulate the lake and confuse NASA’s orbiter.
Mars’ ice has been shown to be much different than how ice is on Earth. Smith says that it doesn’t flow the way you would expect a typical glacier to and that a porous ice could explain that differentiation.
“It would be a big surprise, but Mars is a unique place,” Smith said.
For more on Mars, read about how NASA’s Insight recently landed successfully on the red planet, and more evidence that shows there was life on Mars at one point.
Jessie Wade is a news writer at IGN and thinks there has definitely been life on Mars in the past. Follow her on Twitter @jessieannwade.