We’re still learning new things about the planets orbiting our own star; Yesterday, a group of astronomers announced that mega tsunamis on Mars probably helped shape the Red Planet’s terrain. The researchers were trying to figure out what formed the northern plains on Mars.
For a long time, astronomers thought that the plains were shaped around 3.4 billion years ago by a huge Martian ocean. Problem is, oceans tend to create shorelines with consistent elevations. But the northern plains have geologic features at all kinds of different elevations.
Using a computer model of Martian geology, the team found that mega tsunamis could have created those features, washing water out from the ocean in giant, 120-meter waves.
Asteroid impacts that formed at least two of the craters in the northern plains could have caused these tsunamis — probably about 3 million years apart.
About 3.4 billion years ago, a big meteorite impact triggered the first tsunami wave,
said co-author of the study Dr. Alberto Fairén from Cornell University, Ithaca.
This wave was composed of liquid water. It formed widespread backwash channels to carry the water back to the ocean.
The more recent tsunami would have spread lots of water across the plains, which would have frozen into water ice. Because the ancient Martian ocean was so salty, it probably took tens of millions of years to freeze, which would have been plenty of time for ancient Martian life to establish an ecosystem.
Cold, salty waters may offer a refuge for life in extreme environments, as the salts could help keep the water liquid,
Dr. Fairén said.
If life existed on Mars, these icy tsunami lobes are very good candidates to search for biosignatures.
After all, life can survive in salty liquid water here on Earth. So these ancient ice water deposits could be a great place to look for signs of ancient life — and some of them aren’t too far from where NASA’s Pathfinder mission landed in 1997. Might be time for another trip.