Hunting for fossils isn’t just an Earth-based activity anymore. At least, not in theory. There are a lot of people discussing the possibilities for life on Mars these days, and one of those discussions is about finding evidence of past life. A few people are even talking about finding evidence of current life. But none of our rovers are in place or equipped or even allowed to intentionally look for physical signs of life. Perseverance is in a lake bed, it’s true but is not allowed to venture over to the nearby river delta where microbial life might have been abundant. While there is an agreement to keep spacecraft free of biological contamination, it’s never a guarantee, so scientists act out of an abundance of caution.
Oddly enough, there’s also a push to send humans to Mars so that they can do the research that the rovers cannot. After all, there’s only so much onboard analysis we’ve managed to place on these rovers, and human hands and eyes are an incredible scientific tool. We have a lot of problems to solve before we can send people to the red planet, though. It’s not habitable for us by any stretch. And, as always, one of the things on the checklist is access to water.
New research published in Icarus and conducted by graduate student Shannon Hibbard at Western University in Ontario provides evidence for past ice streams under the surface. Not only that, but the ice streams are in a relatively flat, low-lying region of Mars called Arcadia Planitia, which makes it a potential landing spot for future astronauts. Hibbard explains: We have not seen anything quite like this on Mars, so we look to Earth where streams of ice within ice sheets can exist with no obvious control from surface topography. On Earth, these are known as ice streams.
However, Hibbard and her team cautioned that these results are not evidence of water on Mars. We still don’t fully understand what causes ice streams here on Earth. Hibbard goes on to explain: …it is likely that subglacial water plays an important role in ice stream initiation and flow, especially where surface slope is low, like what we see at the sinuous features in Arcadia Planitia. So, it is possible that at some point subglacial water was present at this location on Mars, but it is unclear how much and for how long.
Western University press release
“Evidence for widespread glaciation in Arcadia Planitia, Mars,” Shannon M.Hibbard et al., 2021 January 9, Icarus