Science

First lake of liquid water discovered on Mars

First lake of liquid water discovered on Mars

Professor Roberto Orosei, from the University of Bologna, wrote in the journal Science: "Anomalously bright subsurface reflections are evident within a well-defined 20-kilometre-wide zone. which is surrounded by much less reflective areas".

Whatever the outcome, the researchers say it would take years to verify whether something is living in the reservoir.

Apparently, the discovery was made using Marsis (Mars Advanced Radar for Subsurface and Ionosphere Sounding), a radar instrument that is used by scientist to study beneath a planet's surface.

The surface is mostly ice and dust for about 1.5 kilometers, but as the radar went deeper the scientists detected a layer that had a particularly bright reflection.

Now, the ISA believes it's found a 20km wide underground lake of liquid water locked under thick ice near the planet's south pole.

The temperature is likely below the freezing point of pure water, but the lake can remain liquid due to the presence of magnesium, calcium and sodium. It stretched about 12.5 miles across and looked very similar to lakes that are found beneath Greenland and Antarctic ice sheets on Earth.

Mars is now cold and dry, but 3.6 billion years ago was home to plenty of liquid water.

Researchers have long suspected evidence of water could be found on the Red Planet, a precursor for life on Mars.

The scientists expect the water is very salty, otherwise it would freeze. NASA found plausible evidence of liquid water in 2015, inspiring inevitable speculation about the red planet being a habitable world.

Most parts of Mars spend much of the time at temperatures too low to support liquid water at the surface.

"Our mantra back then was 'follow the water.' That was the one phrase that captured everything", Hubbard said.

"It's an exciting discovery, if it's true", said Tanya Harrison, Professional Martian and Director of Research for Arizona State University's Space Technology and Science Initiative, who was not involved in this discovery, "since we know that life can survive in subglacial lakes, and brine pockets inside glaciers, here on Earth".

The tool is called the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS), and was created to find subsurface water by sending radar pulses that penetrate the surface and ice caps.

Speaking in a recorded interview released by Science, Prof Orosei revealed that his team spent years checking their results before being confident enough to announce the discovery. He said the announcement might mean scientists pay more attention to what lies below the surface of the cold planet.

However, Stillman, who was not involved in the research, said another spacecraft, or other instruments, need to be able to confirm the discovery.