Water is buried beneath Martian landscape, study says

Sunday, 29 Jul, 2018

Located under a layer of Martian ice, the lake is about 20 kilometers wide, said the report led by Italian researchers in the USA journal Science.

The presence of liquid water on Mars has always been suspected but thus far evidence from MARSIS remained inconclusive. While previous research unearthed possible signs of "intermittent liquid water flowing" on Mars" surface, a new discovery has now braced the possibility of "extra-terrestrial life'.

But most of this water has disappeared into space and the reason is that Mars no longer has global magnetic fields, like Earth has.

Artist's impression of the Mars Express spacecraft probing the southern hemisphere of Mars.

With surface temperatures as low as minus 68C, it would not exist as a liquid under normal conditions. They also analysed the surrounding deposits and temperature of the environment, and believe the highly reflective body is actually a pool of liquid water saturated with salty sediments.

The discovery was made using a radar instrument on board the European Space Agency's Mars Express orbiter, which launched in 2003.

"On Earth, it's nearly a given that if a ground-penetrating radar spots stronger reflections from the sub-surface than from the surface of the polar ice, then you are seeing liquid water". Its ground-penetrating radar detects boundaries between structures of different dielectric permittivity - a measure of a material's electrical polarisation under the influence of an external electric field. "Most importantly, this allows liquid water, essential for life", said Patel. The process requires a detailed understanding of the radar signals that were transmitted downward toward Mars by Mars Express.

"It's probably not a very large lake", says Prof Roberto Orosei from the Italian National Institute for Astrophysics, who led the study.

Water is buried beneath Martian landscape, study says
Water is buried beneath Martian landscape, study says

Either way, the discovery greatly increases the chances of extraterrestrial life existing on Mars.

Scientists have long said Mars could potentially host life, and finding liquid water on the Red Planet is seen as one of the most important aspects of that search for extraterrestrial life.

Billions of years ago, Mars is thought to have had oceans and rivers, much like Earth.

"This is a discovery of extraordinary significance, and is bound to heighten speculation about the presence of living organisms on the Red Planet", said Fred Watson of the Australian Astronomical Observatory.

The presence of water under the Martian polar ice caps has always been suspected but not seen until now, the study said.

Researchers said the lake looked similar to the ones found beneath the Antartic and Greenland. Learning more about these caps can reveal Mars' climate history.

"We found that any other explanation for these very strong echoes was not really tenable in light of the evidence that we had available", he said.

"Maybe this could even be the trigger for an ambitious new Mars mission to drill into this buried water-pocket - like has been done for sub-glacial lakes in Antarctica on Earth", he added.