Now, new research has found more evidence of the lake’s existence, and has also revealed a number of smaller salt “pools” nearby – increasing the likelihood of life on the Red Planet.
Scientists were able to gather more specific details about the lake – for example, they estimate that it is about 30 x 20 kilometers (18.6 x 12.4 miles) in area.
“The existence of a subglacial lake could have important consequences for astrobiology and the existence of habitable niches on Mars,” the statement added.
The ponds – which the study describes as “incomplete ponds or wetlands of smaller areas” – have different sizes, and are separated from the main lake by strips of dry land.
The discovery is important because it gives us a better idea of Mars’ climate and chemical composition. For example, the fact that the lake and surrounding ponds are still liquid indicates that it is “very salty” – meaning that it contains a lot of salt, the study said. This lowers the melting point, preventing the water from freezing despite the cold environment, and possibly allowing them to “survive for a long period of time on a geological scale.”
And of course there is the issue of extraterrestrial life.
A study last year indicated that 3 to 4 billion years ago, Mars – now cold and inhospitable – might have been warm enough to host rolling rainstorms and flowing water, which could create an environment that could support simple life. As the temperatures drop later, the water will freeze.
The latest research suggests that life on Mars may not be just a thing of the past.
“The prospect of the expansion of highly saline water bodies on Mars is particularly exciting because of the potential for microbial life,” the study said.
If there was indeed life in these salt waters, they might take on various forms. Scientists have speculated the possibility of anaerobic organisms – which are microorganisms that do not need oxygen – or tough ones, which can survive in extreme cold or heat.
There can even be air oxides – organisms that require oxygen. The study said salt solutions such as lakes or ponds contain six times the minimum amount of oxygen that microbes need to breathe.
The study concluded that “bodies of water at the base (sediments with antarctic layers) thus represent areas of potential astronomical biological interest and planetary protection concerns,” and it urged future Mars missions to target the polar lake area to collect additional data.