Submitted by marketrent t3_zxbl6v in space
amitym t1_j1zzjc3 wrote
Reply to comment by Austiniuliano in Earth was brought to life by ancient water-rich asteroids from the outer Solar System by marketrent
>there should be oxygen on multiple other planets
There is. There's tons of oxygen, on every planet. Oxygen galore.
It's just all locked up in various forms, like water or CO₂ gas or solid rocks.
It's free oxygen (O₂) that is unique to Earth. And water or not, it wouldn't even exist here if it weren't for living things.
The big question with this new theory is, if these asteroids could have landed all over ... where is all the water on multiple other planets?
Karcinogene t1_j20mjwu wrote
Mercury gets too hot for water, but there is some ice in dark polar craters. Venus has water clouds, but it's also too hot so most of it boiled away. Mars has plenty of water frozen at its poles. According to this article, the asteroid belt would also have lots of ice.
Other than Io, every solid object beyond Mars is completely covered in miles of ice.
There's water everywhere.
amitym t1_j20vqac wrote
Water doesn't just "boil away," though. Boiled water becomes part of the atmosphere. It's still there. Of course in the case of Mercury there is no atmosphere at all anymore. But Venus doesn't have that problem, yet it has only a small fraction of the water Earth has. Unless there's more water hidden somewhere.
Similarly, with Mars, the poles have managed to retain water ice over several billion years without all sublimating away.. so given that water is actually apparently stable on Mars over the very long term, where is the rest of it? Why aren't the polar ice sheets more extensive?
And.. I don't know about every object... the dwarf planets do not seem to be covered in water ice at all. The outer planetary moons probably didn't develop their watery crusts or interiors via asteroid impacts. Although maybe indirectly via water ice asteroid capture?
tarrox1992 t1_j210fz5 wrote
>Pluto is about two-thirds the diameter of Earth's Moon and probably has a rocky core surrounded by a mantle of water ice. Interesting ices like methane and nitrogen frost coat the surface. Due to its lower density, Pluto's mass is about one-sixth that of Earth's Moon.
https://solarsystem.nasa.gov/planets/dwarf-planets/pluto/in-depth/
>We know very little about Eris' internal structure.
>Eris most likely has a rocky surface similar to Pluto
https://solarsystem.nasa.gov/planets/dwarf-planets/eris/in-depth/
The only dwarf planet composition that we are even slightly sure about seems to show that it is, like the other commenter said, covered in miles of ice.
amitym t1_j211l7g wrote
Surface methane and nitrogen ice. Not water ice. Mantle of water ice is not "covered in miles of ice." It's almost the opposite. Pluto looks more like it was an ice asteroid than that it was hit by ice asteroids.
I'm not saying that ice asteroids don't exist. I'm saying that if everything in the solar system got its water from the impact of ubiquitous water ice asteroids, there should be more signs.
Eggplantosaur t1_j23odnf wrote
Should I let the researchers know you figured it out or will you contact them yourself?
amitym t1_j2f5vsz wrote
"Mantle" is the inside, not the outside. I wouldn't think that needs to be explained but here we are.
Austiniuliano t1_j1zzvt2 wrote
Oh, thank you! That is a much more interesting question. I’ll admit that I don’t know enough to ask the right questions but I find space so interesting.
amitym t1_j20060l wrote
I'm sure there are dumb questions in the world but yours was not one of them!
It's not always obvious where this stuff goes, or how things work on other planets. We just recently learned about a whole new kind of natural chemical process when we saw it happening on Venus... until then no one knew that that particular kind of geochemistry was possible. (I forget the details but it was somewhere on this subreddit a while back.)
Grinch83 t1_j22uybg wrote
Okay, I’ll try to throw one of the dumb questions of the world at you…
It’s easy enough to wrap my head around the idea that “x” wasn’t here before, but then a giant rock hurled from space crashed into the planet and brought it here.
But how did we get so much water from this asteroid(s)? In other words, how did we go from a relative puddle of water from the asteroid impact…to 72% of the earth’s surface covered in water?
amitym t1_j22yha5 wrote
Haha still not dumb. So many people wonder about stuff like that, someone made a graphic. Here's a great way to visualize the answer:
Basically... it's less water than you think. Because water, being water, tends to spread out flat. And the Earth is actually pretty smooth.
We think of all these tall mountains and deep chasms and stuff but they're only tall and deep from our human-scale perspective. From the perspective of the whole volume of the Earth, they are the teensiest aberrations. The depths are barely deep enough to get wet.
Grinch83 t1_j230qan wrote
Ahhh, ok ok. Reading your response, I actually do remember hearing Neil deGrasse Tyson saying something along the lines of “if you could hold earth in your hand, at scale, it would feel & appear as smooth as a billiard ball.”
So operating under the assumption that this water asteroid hypothesis is correct, can we also safely assume the asteroid was roughly the size of the largest sphere in the graphic you provided? And all of the water currently on earth came from this event?
Even with your great response and visualization aid, it’s still mind bending to think about! (And that’s not even going into the odds of such an asteroid, making impact with such a planet…and a few billion years later, two descendants of this event discussing it over the internet.)
Awesome stuff; thank you for taking the time to respond! Totally understand if you don’t want to get too deep into the weeds with me here, so no worries on answering the above. But if you have other reading material for me, I’d love it if you could pass it along. I’m super intrigued. :)
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