Liquid water is almost non-existent on modern Mars, but scientists say sedimentary deposits show signs that tsunami waves as high as 400 feet washed over Martian shorelines billions of years ago.
The claim, laid out on Thursday in Nature Scientific Reports, may sound like the Red Planet equivalent of “The Day After Tomorrow,” the 2004 climate-scare movie that showed New York getting drowned. There is a climate angle to the newly published research, but a more apt comparison would be 1998’s “Deep Impact,” in which a crashing comet did something similar.
“The tsunamis could have been triggered by bolide impacts, which, about every 3 million years, generated marine impact craters approximately 30 kilometers in diameter,” study co-author Thomas Platz, a research scientist at the Planetary Science Institute in Arizona, said in a news release about the study.
As spectacular as it sounds, the findings are consistent with how mega-tsunamis happen on Earth, and what scientists expected on Mars as well. There’s lots of other geological evidence that Mars once harbored a large northern ocean. But if that’s the case, there should have been occasional asteroid or cosmic strikes that produced giant waves.