By Sara Muharremi
Last spring, I had written an article debating whether or not Mars was habitable, and if so — would people be willing to buy a Groupon for a piece of land on Mars?
On August 3, in the Nature Geoscience Journal, Western University and the University of British Columbia reported that Mars’ surface and valleys were carved by water melting beneath sheets of glacial ice, not necessarily by free-flowing water, as once thought.
The original hypothesis and assumption described ancient Mars as being a ‘warm and wet’ planet, where the free flowing waters had eroded, creating all the valleys on Mars. On Mars, all the valleys don’t necessarily look the same which therefore depicts that they were carved in more than one type of manner (meaning not just free flowing waters). Similarly, Earth’s valleys are also of distinctive shapes that were made by rivers, glaciers and other processes.
The lead author of this research, Anna Grau Galofre, developed and used new techniques in order to examine thousands of Martian valleys. These valleys were then compared to “subglacial channels” in the Canadian Arctic Archipelago. Similarities were found between the Martian valleys and those of the Archipelago, inspiring the researchers to further their study. In their research they found that Devon Island in the Canadian Arctic serves as the closest comparison we have to Mars on Earth as, “… it is a cold, dry, polar desert, and the glaciation is largely cold-based.”
Further analysis of the Martian valleys yielded results that “… are the first evidence […] that channels and valleys networks can form under ice sheets, as part of the drainage system that forms naturally under an ice sheet when there’s water accumulated at the base.” These findings are revolutionary because they offer a better explanation as to how these valleys could have formed roughly 3.8 billion years ago, on a planet that is situated further from the Sun than Earth, especially during a time where our Sun was not as strong. An ice sheet can also offer increased protection, support, and stability for any water beneath it, which can support survival conditions of any theoretical ancient previous life on mars. And finally, the ice sheet could’ve also offered additional protection from solar radiation since Mars’ magnetic field disappeared billions of years ago.
So maybe an investment in that Groupon would be worth it after all.
Grau Galofre, A., Jellinek, A.M. & Osinski, G.R. Valley formation on early Mars by subglacial and fluvial erosion. Nat. Geosci. (2020). https://doi.org/10.1038/s41561-020-0618-x