LIFE ON MARS
There might be more water on Mars than astronomers think
The discovery of three buried lakes beneath the icy surface of the Red planet further intrigued the researchers
Water has always been considered essential for the existence of life and for a very long time that’s the first thing astronomers have looked for on other planetary bodies to make a connection if life exists there. Not just water, signs of possible life are emerging elsewhere too — the recent discovery of phosphine molecules in Venus’ upper clouds is one such example.
When it comes to finding a habitable planet apart from Earth, our next-door Red neighbor perfectly fits that definition — it sits in the ‘Goldilocks zone’ of our star system, is seismically active, and has traces of magnetic field present, apart from the existence of water ice deposits beneath its surface that we have known since 2008. Later last year, NASA released the detailed Water Ice map of these deposits, made out of the data collected by its Mars Reconnaissance Orbiter.
The search for Alien life and the prospect of habitability of the Red planet got even more interesting earlier this year when astronomers found new evidence of an ancient river on Mars — the researchers concluded that a high rocky cliff in the north-western rim of Mars’s Hellas basin that seems to have been formed gradually by the flow of an ancient river.
“We identified the same body of water, but we also found three other bodies of water around the main one, It’s a complex system… There may have been a lot of water on Mars, and if there was water, there was the possibility of life.”
~ Elena Pettinelli, Co-Author
As if this was not intriguing enough for astronomers, they have now confirmed the existence of a total of four lakes — three from a recent study while confirming the presence of another saltwater lake that was discovered by planetary scientists two years go. The original discovery was met with some skepticism at the time.
Using data from the European Space Agency’s Mars-orbiting spacecraft, Mars Express, the team was able to confirm the current and the previous discovery from 2018. The skepticism surrounding the lake discovered in 2018 emanated from the fact that the claim was based on just 29 observations made from 2012 to 2015. However, the current study has looked at a broader data pool comprising of 134 observations from 2012 to 2019.
Researchers used the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) on Mars Express to scan the Red planet’s southern polar region. The MARSIS instrument sends out radio waves that bounce off layers of material on the planet’s surface and in its subsurface. The reflected signal hints at the kind of material present at any given location.
High reflectivity in some areas indicated towards bodies of liquid water trapped under more than one kilometer of Martian ice. Lakes covered an area of 75,000 square kilometers — with the biggest one at the center measuring measures 30 kilometers across, while the three smaller ones surrounding it came in at a few kilometers in width.
Although the presence of liquid water on the Martian surface is next to impossible due to the lack of atmosphere and extremely low pressure, astronomers have long speculated that there could be water trapped under Mars’s surface — hinting at the possibility of a habitable planet with the abundance of water billions of years ago. This is a pretty distinct possibility, considering we have seen proof of subsurface oceans even in the far reaches of our solar system, like on Saturn’s moon, Enceladus.
Critics still point out that despite the small amount of heat from the Mar’s interior, the presumed subsurface lakes on the planet must have reasonably high salt content for the water to remain liquid — five times that of sea-water can support life. This new discovery has again stirred the debate around the presence of saltwater lakes beneath the Martian surface but not everybody is convinced.
One way to verify the claims made by the researchers in this study can come from the upcoming Chinese Tianwen-1 mission. The mission that consists of a Rover and an Orbiter & carries a bunch of scientific instruments would enter the Martian orbit in Feb. 2021. Let’s keep our fingers crossed.
Complete Research was published in the Journal Nature Astronomy.