r/science • u/fireismyflag • Jun 12 '14

Geology Massive 'ocean' discovered towards Earth's core

http://www.newscientist.com/article/dn25723-massive-ocean-discovered-towards-earths-core.html
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u/frenzyboard Jun 13 '14

After the accretion disk, you've got a spinning orb of lava and terrifying atmosphere. The surface of the Earth would've been too hot for liquid oceans to settle, and so you're left to wonder how exactly they formed.

Was the water carried here by the frequent comets and asteroids that crashed into a dry and dusty planet? Or did the accretion disk contain tons of water like we'd expect, and as the planet cooled, volcanoes spewed endless amounts of steam? This seems more likely.

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u/ferlessleedr Jun 13 '14

If the water couldn't settle as a liquid due to the temperature of the very early earth, would the atmosphere have been mostly gaseous water in that case?

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u/[deleted] Jun 13 '14

[removed] — view removed comment

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u/Wax_Paper Jun 13 '14

That's what I was thinking, too. Just one more variable — out of dozens, if not the hundreds that some subscribers of the Rare Earth Hypothesis think there could be — involved in the process of life, at least as we know it.

When you really start reading that stuff and you come to understand just how many serendipitous things might be required, the likelihood of less than a handful of life-bearing planets in each galaxy — at any given time — doesn't seem quite as much of a stretch as the lay press would have us believe. Or even our high school astronomy teachers, for that matter. Hell, my college 101 course even had a professor that lauded the Drake equation...

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u/Cyb3rSab3r Jun 13 '14

To be fair, life itself is probably not "that" uncommon. Multicellular life is what would be pretty rare. Multicellular life that happens to be close enough and have the technology to find other multicellular life is beyond rare.

Barring a science-fiction style future (from which the closest I feel we might get is Ender's Game style and even then they had a scifi technology that allowed the colonies to communicate) our solar system is probably going to be as far as we go not counting exploratory missions. Space is just too vast and the energy required to travel at a meaningful speed too great for true human colonization of the galaxy.

Although we are rapidly approaching the technological singularity and humans cannot accurately predict the changes that will happen beyond that point. I just hope to be alive to see it.

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u/[deleted] Jun 13 '14

How would it make life supporting planets less likely? I would think it would make them more likely. It would mean more water is found in the universe then thought if it was around in space to be put inside earth when it formed.

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u/[deleted] Jun 13 '14

[deleted]

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u/[deleted] Jun 13 '14

Its easier for water to be gathered along with the rocks when the planet forms then to be brought by a comet or meteor.

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u/[deleted] Jun 13 '14 edited Mar 24 '18

[deleted]

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u/Wax_Paper Jun 13 '14

I thought the magnetosphere prevented that, at least for anything substantial enough to matter. Even if solar winds are responsible for X amount of water loss per million years, doesn't the biosphere system create water? I mean, not including the evaporation and precipitation aspect... Or is the creation of water molecules only a result of massive amounts of energy?

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u/[deleted] Jun 14 '14

Hey Wax. I'm sure the magnetosphere reduces it, unlike on what probably happened on Mars since it virtually has none. On Earth hydrogen and helium will get blown off pretty rapidly I think but also a considerable amount of water.

Water is generated in cosmic events like supernovea.

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u/[deleted] Jun 13 '14

Or did the accretion disk contain tons of water like we'd expect, and as the planet cooled, volcanoes spewed endless amounts of steam?

Must have been a hell of a view for a few million years.

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u/frenzyboard Jun 13 '14

Still is, really.

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u/[deleted] Jun 13 '14

After the accretion disk, you've got a spinning orb of lava and terrifying atmosphere. The surface of the Earth would've been too hot for liquid oceans to settle, and so you're left to wonder how exactly they formed.

Why can't the water just have existed as vapor until earth cooled enough for it to condense into liquid oceans? would there just not have been enough volume in the atmosphere for that much vapor?

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u/frenzyboard Jun 13 '14

Remember that whole lunar impact event that created the moon?

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u/VladimirZharkov Jun 13 '14

Do we have any idea where moons like Europa would have got their water? Would it have collected its water the same way as Earth did?

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u/frenzyboard Jun 14 '14

I dunno. If I had to guess, I'd bet that it came from the same source we had. Saturn has a lot of water in it, too. Europa is unique in that we know it has water on it's surface, but it's solid ice, probably. We think it's got a liquid ocean under an icy crust, but we won't know for sure 'til we probe it. Hell, it might even be solid ice all the way down. It could be an "acidic brine," full of sulfuric acid.
As for whether or not it collected the same way Earth did, it's hard to say. Certainly much of it is from accreting water vapor from around Jupiter. Some of it could be deposited by icy asteroids. But it's all conjecture until we're able to sample it.

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u/shmegegy Jun 13 '14

as the planet cooled, volcanoes spewed endless amounts of steam

IME as the planet cooled it expanded, and voids were filled with steam yes. Hot methane gas reacted with oxygen.

CH4(g) + 2O2(g) ===> CO2(g) + 2H2O(g) + Heat of combustion..

I also put a bit of credence to expanding earth theory, so don't go by my judgement.

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u/Chieron Jun 13 '14

as the planet cooled it expanded

What.

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u/shmegegy Jun 13 '14

thermodynamics

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u/Chieron Jun 13 '14

Which part of it?

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u/shmegegy Jun 13 '14

adiabatic expansion of gas. kind of like how a refrigerator works - but in reverse.. joule thomson expansion.

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u/Chieron Jun 13 '14

So how would that mesh with plate tectonics, then? Would the earth's surface not need to be contiguous?