NASA Rover Discovers Liquid Water 'Ripples' Carved Into Mars Rock (msn.com) 21
Scientists have discovered evidence of ancient, shallow lakes on Mars that once had liquid water exposed to the atmosphere, challenging previous theories that all Martian water was covered in ice. Live Science reports: The patterns, which were photographed by NASA's Curiosity rover, are known as wave ripples -- minute ridge-like structures that form along the shores of lakebeds. This means that exposed liquid water must have flowed across Mars' surface at some point in its history. The ripples were present in two separate lakebeds in Gale Crater, which Curiosity has been exploring since Aug. 2012. "The shape of the ripples could only have been formed under water that was open to the atmosphere and acted upon by wind," study first author Claire Mondro, a sedimentologist at CalTech, said in a statement.
The researchers also analyzed the height and spacing of the ripple waves to determine the size of the lake that formed them. The structures are approximately 0.2 inches (6 millimeters) tall and about 1.6 to 2 inches (4 to 5 centimeters) apart, indicating they were left by small waves. Based on these dimensions, the researchers believe the Martian lake must have been less than 2 meters (6.5 feet) deep. Both dry lakebeds appear to have formed around 3.7 billion years ago, indicating that Mars had an atmosphere dense and warm enough to support liquid water for longer than previously thought -- which could have intriguing implications. "Extending the length of time that liquid water was present extends the possibilities for microbial habitability later into Mars's history," Mondro said. In other words: living organisms may have had a longer window in which they could have evolved on the Red Planet. The findings have been published in the journal Science Advances.
The researchers also analyzed the height and spacing of the ripple waves to determine the size of the lake that formed them. The structures are approximately 0.2 inches (6 millimeters) tall and about 1.6 to 2 inches (4 to 5 centimeters) apart, indicating they were left by small waves. Based on these dimensions, the researchers believe the Martian lake must have been less than 2 meters (6.5 feet) deep. Both dry lakebeds appear to have formed around 3.7 billion years ago, indicating that Mars had an atmosphere dense and warm enough to support liquid water for longer than previously thought -- which could have intriguing implications. "Extending the length of time that liquid water was present extends the possibilities for microbial habitability later into Mars's history," Mondro said. In other words: living organisms may have had a longer window in which they could have evolved on the Red Planet. The findings have been published in the journal Science Advances.
How do ripples lithify? (Score:1)
Why wouldn't ripples erode in the wind before getting "baked" into rock, if that's how it happens?
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Is it provocative that I went full jeopardy on the internet probably three years ago now?
Re:How do ripples lithify? (Score:4, Informative)
Why wouldn't ripples erode in the wind before getting "baked" into rock, if that's how it happens?
Where I live, I'm surrounded by sandstone formations that include fossilized beach ripples. They get preserved as is after landslides and other sudden events bury the ripples before they have a chance to erode.
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Can you simulate a landslide by dumping rock of your choice on a beach; then if you carefully remove it, will the underlying ripple marks be perfectly preserved? Or will the landslide flatten the sand?
Re:How do ripples lithify? (Score:4, Informative)
The same way it happens on earth. Planetary geologists spend as much time studying earth analogs as they do the features of planetary bodies. We have lots of examples of sedimentary rocks with water ripples in them in earth and we have a pretty good handle on how they formed (and are presently forming in mud flats) and most likely they formed under similar conditions on Mars.
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Can you please point me to examples of water ripples presently lithifying?
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I'm not a geologist so I don't know the specifics. But I have worked with geologists and they have shared a bit of their knowledge. Any place where there is shallow water and silt ripples can form from wind in the silt. The water dries up and the silt turns hard and dry, often preserving the ripples, at least for a while. I can see that in mud puddles. If they got covered in some way they would "lithify" eventually. I imagine most places where you'd see ripples forming, including my mud puddles, would
Re: How do ripples lithify? (Score:2)
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Are you telling a just-so story about how mud might fill in over sand ripples without distorting them? What if the ripples were fused suddenly (hot ash?) rather than lithifying over the long periods imagined by geologists? What if lakes dried up and sand fused into rocks on a much quicker scale than currently envisioned?
Re: How do ripples lithify? (Score:2)
Ripples found on Mars (Score:2)
What flavor were they?
Re: Ripples found on Mars (Score:2)
Mars Has Water (Score:1)
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We're going to build a big, beautiful resort on Mars. It will be amazing. Just amazing. We'll even ship in illegal labor from the rest of the world, because they have to go somewhere and we don't want them here. I hear it's a little cold on Mars, but that's why we're going to invest in huge furnaces powered by big, beautiful coal. It will be fabulous, just fabulous. We can call it the Riviera of the solar system. That's what we'll call it. And ammonia is a big greenhouse gas, so we'll ship Kamala up there t
Video of moving water (Score:2)
...or it didn't happen!
Re: Video of moving water (Score:2)
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> horse shoe crabs without tails
My theory is ancient Romans found the tails delicious, but not the rest, and desperate tail-free crabs gravitated toward the shore where food was more plentiful, but so were predators, and wall builders.
I don't dispute there was probably flowing water on Mars once, but scientists generally concluded that decades ago. Any new evidence is merely incremental reinforcement of that theory, not revolutionary.
X-Files had it figured out a long time ago. (Score:2)
It's just a Martian alien's wet fart.