Scientists detect an underground lake filled with liquid water on Mars

Today, there’s little doubt that Mars once had liquid water on its surface at some point in its history. For example, the Curiosity rover has provided evidence pointing to this conclusion by mineralogical studies of sediment samples collected and carried out at Gale Crater. But although contemporary Mars appears inhospitable and dry as a bone, scientists have recently announced that liquid water may be nestled in some pockets beneath the surface of the Red Planet. The latest findings reported by researchers at the Italian Space Agency suggest that a 20 kilometer-wide subglacial lake lies just 1.6 kilometers beneath the surface, near the south pole of Mars.

    “This is just one small study area; it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered,” said lead-author Roberto Orosei in a statement.

The monumental discovery of subterranean liquid water was performed with ground-penetrating radar (GPR) on the Mars Express spacecraft, a European Space Agency (ESA) probe that has been orbiting Mars since 2003. GPR works by sending electromagnetic waves towards the ground and timing how long it takes for them to return. The travel time is dependant on the material through which it passes, so this way we can figure out what kind of materials lurk beneath a surface without viewing it directly. The technology was initially developed so the military could locate mines, but today, GPR is used in all sorts of applications, such as finding avalanche victims, micro-fissures in constructions, small archaeological objects — and, now, water on Mars!