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marketrent OP t1_j1zc2a7 wrote

Laura Bandell, 19 December 2022.

Excerpt:

>Earth formed in the dry inner Solar System. It would have remained inhospitable and lifeless, had water not been transported to it by asteroids that originated in the outer Solar System.

>Using world-class oxygen isotope analysis facilities at The Open University (OU), an international team (Team Kochi) has been studying precious samples returned to Earth in 2020 from asteroid 162173 Ryugu by the Japanese Space Agency (JAXA) Hayabusa2 spacecraft.

>The results of this new study clearly show that the Ryugu particles are a very close match to a rare group of water-rich meteorites known as the CIs (Ivuna type)1. CIs are extremely fragile materials and normally fragment during atmospheric entry and so, generally, fail to make it to the Earth’s surface as recoverable samples.

> 

>Identification of asteroid Ryugu as a CI-type body suggests that this group is much more widespread amongst the asteroid population than its limited presence in our meteorite collections suggests.

>This new finding has important implications for how Earth got its water, because CIs are also the most water-rich meteorite group we know of.

>Dr Richard Greenwood, who led the analysis work at the OU explains further:

>”Our results demonstrate that the material collected from asteroid Ryugu is closely similar to the composition of those early hydrated asteroids that brought life-giving water to Earth. In a very real sense, these “killer” asteroids saved planet Earth.”

Nature Astronomy, 2022. DOI: 10.1038/s41550-022-01824-7

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Austiniuliano t1_j1zk1if wrote

This is dope. Can someone explain tho. If water is in asteroids which is H2O… wouldn’t that mean the O has to come from somewhere else. I get that it is most likely formed from nuclear fusion and an exploding star.

But that would mean these asteroids that form could have landed all over and there should be oxygen on multiple other planets.

So like more evidence that life should be on other planets correct?

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Chichachachi t1_j1zl6ch wrote

All the oxygen on earth was pulled out by bacteria. The earth was anaerobic until about 2.5 billion years ago, when bacteria started to excrete oxygen as waste. We got to high levels by about 2 bya. Also, oxygen is toxic and it's why things rust and why our skin ages so quickly. But it's like rocket fuel so life took advantage.

https://en.m.wikipedia.org/wiki/Great_Oxidation_Event

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HerbaciousTea t1_j205ob8 wrote

The great oxidation event likely also triggered a massive planet wide extinction event, since oxygen is so reactive.

I think there's a pretty good argument that an oxidation event is one of the hard steps that could comprise the Great Filter.

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guynamedjames t1_j205odu wrote

Yup, while free atmospheric oxygen is technically stable it's very reactive with most things, especially when you give it a little energy. Since life requires a ton of complex and ever changing chemical reactions to take place it really helps to have a reservoir of a very reactive substance around at all times. This also means that most atmospheric oxygen is one half of a reaction to free up chemical potential energy. So having an atmosphere made of half a battery isn't a bad thing either when talking about complex life.

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kobeyoboy t1_j1zwitr wrote

So Stop Breathing to keep skin young? Thanks

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-BrilliantParking- t1_j206x2l wrote

More like cover yourself in cling film to keep your skin young

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GeauxAllDay t1_j20bk2o wrote

Oxygen is good for your lungs but bad for your skin

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PeakFuckingValue t1_j20kjz0 wrote

Maybe going aquatic will dilute it enough. It's gill time

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fyigamer t1_j23rp7i wrote

Oddly enough several sea creatures do live a very long time. I wonder if this is why

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dion_o t1_j213bpx wrote

Been doing that for years boss.

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Dantexr t1_j27fz60 wrote

I think that if you stop breathing you will not age anymore

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Rhondajeep t1_j22zjqs wrote

What would happen if we transplanted those organisms to Mars, could we ADD oxygen to another planet?

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Austiniuliano t1_j24mik1 wrote

There is a cool animated explanation and that is one of the steps. https://youtu.be/HpcTJW4ur54

Short answer is we would need to to Teriform mars but one downside is that a disease could wipe out a whole species and throw off the balance. So it would be doable but difficult

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Frankeman t1_j283l5m wrote

To my understanding: yes, but there are two major problems:

  • You'll need a huge number of bacteria to make a difference. Even doing that on Earth will be tricky. What helps of course us that they multiply themselves, but it will take a while nevertheless
  • The atmosphere of Mars is very thin due to the absence of a magnetic field. Even if you are able to produce much oxygen, most of it will get ionised by radiation and will be lost eventually

However, the bacteria themselves should be able to survive out there on Mars, if not thrive. They are crazily resilient

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Yellow_XIII t1_j225kd3 wrote

So you're telling me the very atmosphere we need to sustain life and the very air all animals breathe... is nothing more than bacteria farts?

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Bascna t1_j22bw0o wrote

Yep. Those little critters were serious terraformers.

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Maezel t1_j26xn8z wrote

Oh the circle of life... Bacteria oxygen waste triggers a massive extinction. A few billion years later, lifeforms that benefit from oxygen and produce co2 waste trigger another massive extinction.

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amitym t1_j1zzjc3 wrote

>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?

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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.

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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?

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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.

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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.

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Eggplantosaur t1_j23odnf wrote

Should I let the researchers know you figured it out or will you contact them yourself?

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amitym t1_j2f5vsz wrote

"Mantle" is the inside, not the outside. I wouldn't think that needs to be explained but here we are.

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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.

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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.)

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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?

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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:

https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/thumbnails/image/all-the-worlds-water.jpg

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.

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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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85423610 t1_j1zkv1w wrote

Yes you are right, however oxygen & Hydrogen would still need the right conditions to maintain long enough for life to evolve. Also radiation is a big factor. And many more.

But yes, this would in theory reflect a higher probability of planets having water resources avaible even though we would believe it wouldnt be the case from formation. Then we move onto the questions of what does a planet require to maintain it +what ither pre-quistes are there for life.

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citro-naut t1_j227r75 wrote

Most of the oxygen on earth is locked away in the rocks and minerals that make up the earth itself! The free oxygen in the earths atmosphere is almost entirely created by life. The first life forms on earth were not aerobic and didn’t use oxygen to metabolize.

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FluffyGarbage23 t1_j20gc4g wrote

What I dont get is how many (or big) asteroids would've had to cross its path with Earth, enough to create all the water that eventually enabled life to exist. Theyre not exactly water balloons filled to the brim with water.

How much water is in an asteroid, and how many did make it through the atmosphere? Earth must've been bombarded every second for however many years, and likely other planets like Mars as well.

Except Mars had a different fate than ours unfortunately.

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tarrox1992 t1_j20jlvl wrote

https://solarsystem.nasa.gov/planets/dwarf-planets/ceres/in-depth/

Ceres could be up to 25% water.

https://www.usgs.gov/media/images/all-earths-water-a-single-sphere

An asteroid (well, it'd be a dwarf planet) composed only of water-ice with the same mass of Earth's water would, presumably, be slightly larger than those spheres. Because water expands as it freezes and a dwarf planet would be at least partially frozen.

https://upload.wikimedia.org/wikipedia/commons/1/16/Ceres_Earth_Moon_Comparison.png

So, looking at the size of Ceres compared to Earth/Earth's water, I'd assume that we'd only need 5-6 bodies similar to Ceres to fill us up.

https://solarsystem.nasa.gov/moons/jupiter-moons/europa/in-depth/

They think there is more than twice the amount of water on Europa than on Earth. Not even mentioning the other very wet moons of the outer planets. The article here believes Earth water came from the outer solar system, and, looking at all the information here, it should be easy to see that some asteroids are basically water balloons. Even if they aren't, there are still plenty of water rich bodies the Earth could have amassed.

edit: typos

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citro-naut t1_j228qqb wrote

While we don’t know for sure, water probably makes up something like 0.05% of earths mass, which is not that much at all! And in fact, you can easily acquire this much water by only accreting the driest types of planetary building materials (eg enstatite chondrites) without needing any contribution from the water-rich bodies discussed in this article. Though, these water-rich bodies almost certainly did deliver some fraction of earths volatiles!

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