Asteroid Crashes Likely Gave Earth Its Water 138
Diggester writes "Asteroids from the inner solar system are the most likely source of the majority of Earth's water, a new study suggests. The results contradict prevailing theories, which hold that most of our planet's water originated in the outer solar system and was delivered by comets or asteroids that coalesced beyond Jupiter's orbit, then migrated inward."
Sounds intelligently Designed (Score:3, Funny)
So rocks carrying massive amounts of water magically came to the Earth?
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Now we need to find a way to crash land a comet into mars.
So we can get our ass to mars.
Re:Sounds intelligently Designed (Score:4, Interesting)
Better yet, crash Ceres into Venus. A 9.43 ± 0.07×1020 kg mass crashing at 10 miles per second would probably blow most of the atmosphere off and Ceres is largely water.
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Better yet, crash Ceres into Venus. A 9.43 ± 0.07×1020 kg mass crashing at 10 miles per second would probably blow most of the atmosphere off and Ceres is largely water.
You nerds scare me.
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I'm pretty sure that Ceres is heavier than ten tonnes.
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OK, with you so far.
does Slashcode not know how to handle either this 10^20 exponent operator, or this one 10**20? Or is your keyboard set up to post some non-Latin characters?
Whatever about bloody Slashcode!
do you care to quantify "most of the atmosphere"? My back of the thumbnail estimate is that the 487km diameter Ceres would carve an initial crater some
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So we can drop off the OP on the way to the stars?
It's Turtle piss, mostly. (Score:5, Funny)
The four Elephants contributed a lot less.
Humanity's very existence is proof against Intelligent Design.
Re:Sounds intelligently Designed (Score:5, Informative)
Frozen rocks basically, but yes.
They slammed into earth.
Watch some Discovery or read some books some times.
This is nothing new.
What may be new, is the fact that these asteroids may be from further away than first anticipated.
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Since when does crash imply a plan and an accident? Who planned the crash of the waves against the shoreline?
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God did. And still does, everyday.
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Actually, not frozen rocks in this case. That was the old theory.
Here, the deuterium ratios match that found in chondrites from the inner solar system (they estimate the asteroid belt area), and that these then broke down, giving up oxygen and hydrogen, which then formed water.
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Expected it to be +1 Funny
Is +1 Insightful
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How many asteroids does it take to give us the water we have?
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Close, but not quite. What the article is saying is that rocks carrying massive amounts of water naturally came to the Earth.
PS All non-zero amounts of water are massive.
Re:Sounds intelligently Designed (Score:4, Funny)
So rocks carrying massive amounts of water magically came to the Earth?
Yes, and the Intelligent Designer's son turned some of it into wine.
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Which, if true, makes his death a crime against humanity. A source of wine cheaper than water...;-)
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Re:Sounds intelligently Designed (Score:4, Informative)
Some people call it gravity.
Note: Earth has about 0.1 - 0.01 % water by mass (depending on how much water you think there is in the mantle). Compared to the outer solar system (typically 50%) it's not _that_ massive.
Re:Sounds intelligently Designed (Score:4, Funny)
If you consider gravity to be "magic", then yes.
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42
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Ultimately, I don't know if I consider anything to be magic. If you could give me absolute proof of fairies in the bottom of the garden who make the flowers grow, I would be amazed, but I would also consider them to be part of the natural world. I would be extremely interested in how they could be reconciled with our existing knowledge, theories and observations.
In any case, how gravity works at a fundamental level is pretty much irrelevant to the discussion. We know that gravity works and that we can know
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Please be patient while we work on what you belive is a work of fiction conflicts with your work of fiction.
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I think the intelligent design stroke is in making such asteroids STOP hitting the earth.
Jokes aside: an eternal creator can create a world populated with creatures with free will, completely random interactions, no interference from the creator itself, that ends up EXACTLY how the creator wished. Because the creator creates time too, he is not bound by it. I am not saying this world has random interactions, a creator, free will. I am saying that even by our restricted logic, the creator and the nature of c
The Weekend Genesis (Score:2)
One day the Earth was so thirsty it asked Space for a drink. Space provided with a steady stream of nicely iced drinks. Eventually the Earth became so drunk that all kinds of creatures appeared.
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Nothing magic about this. These asteroids probably hit during the late, heavy bombardment. According to the Nice model, this is a result of Jupiter and Saturn being in an orbital resonance (Jupiter orbiting once for every two times Saturn orbited). A number of scientists (notable among them, WF Bottke), speculate that the Hungaria family of asteroids was nearly completely depopulated that this time as most were knocked into the inner solar system.
A recent discovery of an 100 km diameter, 2 bya asteroid cr
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When the Earth was first being formed, the whole region of the nebula was far to hot for water to condense. So, the original rock was mostly just heavy metals and such.
A little further away from the sun, the relative abundance of hydrogen and oxygen made for excellent conditions for the formation of water, which eventually became huge icy asteroids. They are still out there, in fact. Some of them crashed into the Earth though, where the water melted and became our oceans.
That is, of course, an oversimpli
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Where did the ice come from on the asteroids? Were they hit by little wet Earths?
As you must know (or maybe not) water is made of two hydrogen atoms and one oxygen atom. By mass, that means that oxygen is 16 parts oxygen and 2 parts hydrogen. Now, hydrogen is quite simply the most abundant element (from the regular periodic table anyway, who knows if any of the dark matter takes forms that could be classed as "elements") in the entire universe. As a single proton with a single electron, it's the simplest, most basic stable form of baryonic matter. As for the oxygen, it's estimated to be
GOD DID IT !! (Score:1)
That's the simplest explanation. You nerds and your crazy ideas !!
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That's the simplest explanation. You nerds and your crazy ideas !!
Best possible explanation for unplanned pregnancies.
How did the water get on the asteroids? (Score:3)
Hmmm.
Also it must have been hit by a whole heck of a lot of spacerocks, since 2/3rds of the surface is water. That's a lot of impacts.
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Re:How did the water get on the asteroids? (Score:5, Informative)
It looks like a lot of water, but it's mostly on the surface so it is misleading. Here's a neat graphic. [abovetopsecret.com]
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Wow, that is am impressive graphic. Thank you.
I was aware that the atmosphere was extremely thin relative to the earths diameter.
But I had no idea the total water volume would be even less than that!
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That is cool. I wonder how big a sphere all the humans would make. And then all the biomass.
Yes, it would (Score:5, Informative)
According to quick Google, average depth of oceans is about 4km, surface area of earth is about 510'072'000 km2 and water covers about 70% of earths surface.
5.1E8 km2 * 4km * 0.7 = 1.428 billion km3. Sphere of that volume is about 1396 km across.
The GP's graph says "1390 kilometres across and has a volume of 1.4 billion cubic kilometres", which is very close to that quick approximation.
My approximation is very quick and dirty (I didn't take into account that surface of earth is less 4km below the surface than on the surface, which would reduce the sphere... but I also didn't take into account glaciers, etc. which would increase the sphere... Obviously the surface of sea isn't exactly 70% and the depth isn't exactly 4km...) but I feel very confident that the scale of the number is about right and it happens to perfectly match the graph.
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But formula confirms
V = 4/3* pi* r^3
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The Earth was hit by a whole heck of a lot of spacerocks. That's settled knowledge.
What isn't settled is if the internal rocks were carrying enough water, or if nearly all of it came from the outer parts of the Solar System.
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The moon (Score:3)
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No. The earth and the moon formed in drastically distinct environments. The earth was congealing out of the accretion disk and only later was the moon knocked off from our not-quite-solid self. The moon does have more lighter metals than we do.
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Re:The moon (Score:4, Interesting)
The moon has lower gravity than earth and little or no atmosphere for all of its history. Any water on the surface of the moon would be expected to be stripped away by by the solar wind over millions of years, leaving only deposits in shielded locations. Some water would also be created on the moon from the solar wind as well. I think we should reasonably expect with those conditions and that amount of time that the concentrations of water on Earth and on the moon would be nothing alike.
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Maybe, but I would imagine the moon would experience a much greater amount of water loss into space. If one could estimate the differing rates, then maybe the moon could provide another line of evidence.
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Liquid water does not last long on the moon; the solar radiation boils it away. There could still be water on the moon, though, but our missions there have still barely scratched the surface (so to speak).
If you are really curious, you could just type the word "moon" into wikipedia. There is a lot of info there.
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But the inner solar system asteroids from the time period we're talking about would have had a lot more water. Over billions of years, it will have mostly sublimated away and been pushed right out of the solar system or collected in the outer solar system.
not really surprised (Score:2)
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Re:Just my own musings... (Score:4, Insightful)
If I was the creator of the universe, and had billions of trillions of planets capable of supporting life, what would be the most efficient 'delivery system' for me to use to deliver the "Seeds of Life" to them all?
If you can create universes, you don't need "delivery systems". You just speak your will into being.
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So, if life sprouted on this planet, it stands to reason it's happened everywhere. Ergo, we most likely are not 'alone'.
Continuing that line of thinking, you may find these two articles interesting:
http://en.wikipedia.org/wiki/Fermi_paradox [wikipedia.org]
http://en.wikipedia.org/wiki/The_Great_Filter [wikipedia.org]
My apologies if you're already familiar with these concepts.
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Not necessarily. Water is only one tiny part of the requirements for life (as we know it). Of course it is possible, theoretically, for life to exist in other situations, but that is all we have: theory.
Before anyone points out that life on Earth has adapted for situations well outside the normal range of Earth life (high radiation or temperatures, for example), the key word there is "adapted". In other words, such life is able to exist because the Earth overall is a fairly easy environment for life to dev
Can somebody please explain..... (Score:2)
Why is it that water had to come from elsewhere, exactly?
I mean, if it could form on comets or asteroids, why could it not have formed right here on Earth the same way it forms elsewhere? Why is there such a predisposition to the notion that water must have come from somewhere else?
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A few things:
1) When the Earth was being formed, it was smaller than it is now (not having been fully formed yet, and all). So, the gravitational field was lower. Lightweight stuff would have had a much easier time escaping, especially with the nice hot solar wind blowing.
2) Given the lack of our current atmosphere, the direct exposure to solar radiation would have been intense enough to actually separate the water out into its basic elements. The separated hydrogen and oxygen would have been even lighte
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Earth, in its early years, was a molten ball of rock and metal. Pretty much all the junk that's swirling around in the mantle today, plus the stuff in the crust that floated to the top. Think Jupiter's moon Io, but bigger, and it eventually cooled off. Anyway, when a planet is that hot
Neon (Score:2)
Why is it that water had to come from elsewhere, exactly?
The reasoning can be summed up in one word: Neon. There is almost none of it on Earth, although it is common elsewhere in the Universe, and was almost certainly common in the cloud that formed the Earth and Solar System. Neon has an atomic mass of 20. Water is 18. So when the Earth was young and hot, and didn't have enough gravity to hold onto its neon, it wouldn't have been able to hold onto water vapor either. Therefore the water must have arrived later.
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One question remains, however... why did water arrive, but not any Neon?
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One question remains, however... why did water arrive, but not any Neon?
The early Earth lost both its water and its neon because it was very hot from massive collisions. For instance, the collision that is believed to have formed the moon was enough to liquify the entire planet. But comets and asteroids were never hot. So they lost their neon (which is a gas at even very low temperatures) but didn't lose their water because it was frozen.
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1. There is a lot more of Hydrogen and Oxygen than Neon.
2. Water have a feezing point of 273.15 K, while neon is 24.56 K(Under standard pressure, but it doesn't change much). This means that water can form a solid closer to the sun, and crash into things like Earth instead of just get blown away by solarwind.
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Time to paint a big bullseye on Venus (Score:1)
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Obligatory post (Score:1)
Ok, just to get it out of the way, here's the obligatory question: This happened millions of years ago! How is it news for nerds?
p.s. anyone who answers this as if it were a legitimate question shall be dunked into a tank full of melted asteroids. :)
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Desert world (Score:1)
Yet Earth, in terms of its overall mass, is 0.06% water [nature.com]. With about 70% [usgs.gov] of its surface covered in water, Earth is considerably drier than it appears.
It originated from our fucking sun, morons. (Score:2)
http://news.nationalgeographic.com/news/2011/06/110613-space-science-star-water-bullets-kristensen/ [nationalgeographic.com]
Done and done. It's shown that most stars do this.
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Your statement does not contradict what the article is saying. Did you intend it to?
Everything heavier than hydrogen is cooked within and then ejected from a star. Stars are where atomic fusion occurs, you see.
The water droplets shoot out from the poles of the star. They are perpendicular to Earth's orbit. So, those droplets wouldn't have landed directly on the Earth. They first would have frozen out in the void of space, and collapsed into one another due to their mutual gravity, forming big icy rocks
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>implying people RTFA when we like to go by what should be a fucking accurate title and body of a summary.
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also from the core (Score:2)
I once had a quick-link to a paper on the topic – but there is a fringe of geologists that speculate how water could from from liberated oxygen and hydrogen deep within the mantle. Basically, the earth 'sweating' water from the core, outward.
It hard to imagine (statistically) that all of earth's water... such a huge volume, was from icy balls (comets) striking the planet.....
absolutely ridiculous! (Score:2)
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It sounds like you formed a conclusion before reviewing the evidence.
Do you realize that the Earth is less than one tenth of one percent water by mass? Plenty of asteroids have more water than that.
Also, during the formation of the Earth, the region anywhere under 4AU from the Sun was so hot that water could not condense. Direct exposure to solar radiation of that intensity actually makes water break down to its basic elements, so you wouldn't get any as a core part of the planet. A bit further out, howe
Here, there... (Score:2)
Whatever. We got the water- Mars can suck dust. Take that you funny looking green guys!
oh, Asteroid, not Android (Score:1)
At first I read that as "Android crashes" and wondered if only there were some way to harness the power of Windows crashes as well....
Title wrong (Score:2)
Whoever wrote 'Asteroid Crashes Likely Gave Earth Its Water' as a news headline should not be allowed to write headlines anymore.
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I love Space Nutter Butters.
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So, the idea that most of the Earth's water came from the outer solar system as opposed to the inner solar system is one of the main points of the "religion" of the people you refer to as "Space Nutters"? You seem to have a pretty serious psychological disorder there yourself.
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Reality and statistics says that there's a pretty good chance that an asteroid or comet strike big enough to potentially wipe out our species will happen again. If we are still around when it happens and we don't have sufficiently advanced space tech (either for colonizing other planets or for deflecting the comet/asteroid or both) then we certainly could be wiped out. Chances are miniscule that it will happen in our lifetimes, but if we manage to survive as a species for tens of millions more years, it's
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the heavier deuterium will wind up sinking into the part of the cloud that becomes part of the star
Though deriving from simple principles, it is not that simple- accretion happens in at least two distinct spatial scales: the loose, yet gravitationally bound 'cloud' (called an 'envelope') is feeding the accretion disk. This envelope's size is of the order of ten or twenty thousand Astronomical Units [wikipedia.org] (1 AU = distance from Earth to Sun), and takes forever to 'collapse'; the accretion disk, in turn, is feeding the central object, is much denser, and things happen faster. Typical sizes for the accretion disk
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they were never, say, part of an ancient planet, and then broke-off: they formed as rocks
Actually, some have been parts of larger bodies: it is these ones [wikipedia.org] that haven't, but these are not mentioned in TFA or the publication.
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Asteroid impacts are neither good nor bad. They are just natural events.
An asteroid impact on Earth today would kill a lot of people, so we can be forgiven for thinking of that as bad. But back when there was no life on Earth, the impacts mostly just increased the Earth's mass (and delivered a little water). THOSE turned out to be good for us today because they helped set the stage for our evolution.