An Ancient Asteroid Impact May Have Caused a Megatsunami on Mars (gizmodo.com) 16
The Viking 1 lander arrived on the Martian surface 46 years ago to investigate the planet. It dropped down into what was thought to be an ancient outflow channel. Now, a team of researchers believes they've found evidence of an ancient megatsunami that swept across the planet billions of years ago, less than 600 miles from where Viking landed. Gizmodo reports: In a new paper published today in Scientific Reports, a team identified a 68-mile-wide impact crater in Mars' northern lowlands that they suspect is leftover from an asteroid strike in the planet's ancient past. "The simulation clearly shows that the megatsunami was enormous, with an initial height of approximately 250 meters, and highly turbulent," said Alexis Rodriguez, a researcher at the Planetary Science Institute and lead author of the paper, in an email to Gizmodo. "Furthermore, our modeling shows some radically different behavior of the megatsunami to what we are accustomed to imagining."
Rodriguez's team studied maps of the Martian surface and found the large crater, now named Pohl. Based on Pohl's position on previously dated rocks, the team believes the crater is about 3.4 billion years old -- an extraordinarily long time ago, shortly after the first signs of life we know of appeared on Earth. According to the research team's models, the asteroid impact could have been so intense that material from the seafloor may have dislodged and been carried in the water's debris flows. Based on the size of the crater, the team believes the impacting asteroid could have been 1.86 miles wide or 6 miles wide, depending on the amount of ground resistance the asteroid encountered. The impact could have released between 500,000 megatons and 13 million megatons of TNT energy (for comparison, the Tsar Bomba nuclear test was about 57 megatons of TNT energy.) "A clear next step is to propose a landing site to investigate these deposits in detail to understand the ocean's evolution and potential habitability," Rodriguez said. "First, we would need a detailed geologic mapping of the area to reconstruct the stratigraphy. Then, we need to connect the surface modification history to specific processes through numerical modeling and analog studies, including identifying possible mud volcanoes and glacier landforms."
Rodriguez's team studied maps of the Martian surface and found the large crater, now named Pohl. Based on Pohl's position on previously dated rocks, the team believes the crater is about 3.4 billion years old -- an extraordinarily long time ago, shortly after the first signs of life we know of appeared on Earth. According to the research team's models, the asteroid impact could have been so intense that material from the seafloor may have dislodged and been carried in the water's debris flows. Based on the size of the crater, the team believes the impacting asteroid could have been 1.86 miles wide or 6 miles wide, depending on the amount of ground resistance the asteroid encountered. The impact could have released between 500,000 megatons and 13 million megatons of TNT energy (for comparison, the Tsar Bomba nuclear test was about 57 megatons of TNT energy.) "A clear next step is to propose a landing site to investigate these deposits in detail to understand the ocean's evolution and potential habitability," Rodriguez said. "First, we would need a detailed geologic mapping of the area to reconstruct the stratigraphy. Then, we need to connect the surface modification history to specific processes through numerical modeling and analog studies, including identifying possible mud volcanoes and glacier landforms."
"Alien environments be alien." (Score:3, Insightful)
Some day people will live on Mars, and weird/scary shit will be way better documented there. Fifty-mile-wide tornadoes (though not very strong in force, due to weak atmosphere)...or when there's liquid from human engineering, terrifyingly steep waves...or landslides that seem to go on and on...
But it's "all in the game." If you want there to be a game.
Re:"Alien environments be alien." (Score:4, Informative)
Re: (Score:2)
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If you RTFS (or worse, read the actual paper - you've seen the link - specifically fig 4d and 4e), you'd see they're modelling the Viking-1 site being several hundred metres above the level of t
Mars is Dead (Score:2)
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Mars is a dud of a planet, and this just proves it. A crater from 3.4 billion years ago, and it's still visible? If that happened to earth it, would've been erased long ago. There are much more interesting places in our solar system to study than Mars.
For enough water to exist to form a mega-tsunami, there was a crater-wearing atmosphere wrapped around it at some point. Not unlike Earth. Ironically enough, that impact may have been one of the events long ago that destroyed that ecosystem, creating a dead planet and atmosphere, which would then wear on crater impacts about as well as our own moon does.
Sounds interesting, particularly considering we're the only waterlogged blue dot sitting in the same cosmic pinball machine able to sustain human life ri
Re: Mars is Dead (Score:1)
A crater from 3.4 billion years ago...
They think it's that old. If they're off by a couple orders of magnitude (Mars shouldn't have had its topography altered too much since then, at least according to the prevailing theories), it might have been caused by whatever left its atmosphere full of non-natural Xenon ~200 million years ago.
Of course, it's a lot easier to just ignore the [discomforting] holes in the narrative and not ask such questions.
Jumping the gun (Score:3)
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1) What's wrong with that?
2) This explains some of the weird water drainage patterns seen in the area of the Viking landers.
Ancient Apocalypse (Score:1)
That's yuuuuuge! (Score:2)
Wow. Most Tsunamis don't reach across a whole continent, let alone to a planet as far away as Mars.
May have (Score:2)
May have. Let me know when the answer is "did."