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138 comments

Sounds intelligently Designed (3, Funny)

gameboyhippo (827141) | about 2 years ago | (#40656663)

So rocks carrying massive amounts of water magically came to the Earth?

Re:Sounds intelligently Designed (2)

binarylarry (1338699) | about 2 years ago | (#40656681)

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 (0)

Anonymous Coward | about 2 years ago | (#40656841)

"So we can get our ass to mars."

Who is this "we"? And why?

Re:Sounds intelligently Designed (3, Interesting)

dryeo (100693) | about 2 years ago | (#40657723)

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.

Re:Sounds intelligently Designed (1)

Anonymous Coward | about 2 years ago | (#40659093)

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.

It's Turtle piss, mostly. (5, Funny)

Grog6 (85859) | about 2 years ago | (#40656715)

The four Elephants contributed a lot less.

Humanity's very existence is proof against Intelligent Design.

Re:It's Turtle piss, mostly. (0)

Anonymous Coward | about 2 years ago | (#40656725)

Elephants provided the dung that made continents. Duh.

Re:It's Turtle piss, mostly. (0)

Anonymous Coward | about 2 years ago | (#40656873)

It's turtle piss all the way down.

Re:Sounds intelligently Designed (4, Informative)

Tukz (664339) | about 2 years ago | (#40656743)

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.

Re:Sounds intelligently Designed (1)

Anonymous Coward | about 2 years ago | (#40656869)

The title says 'crash' which implies a plan and an accident, therefore intelligent design. I think collision would be a more appropriate term.

Re:Sounds intelligently Designed (1)

Daetrin (576516) | about 2 years ago | (#40657635)

Entirely correct, except that what may be new now is that those asteroids may _not_ be from further away than first anticipated.

Re:Sounds intelligently Designed (1)

Impy the Impiuos Imp (442658) | about 2 years ago | (#40657653)

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.

Re:Sounds intelligently Designed (1, Insightful)

schitso (2541028) | about 2 years ago | (#40656757)

Saw that this was modded up.
Expected it to be +1 Funny
Is +1 Insightful
:(

Re:Sounds intelligently Designed (1)

Anonymous Coward | about 2 years ago | (#40656823)

How many asteroids does it take to give us the water we have?

Re:Sounds intelligently Designed (0)

Anonymous Coward | about 2 years ago | (#40657045)

From my extensive digital research on the subject some years back, I concluded that you want to begin with at most a couple of ice comet impacts for your standard-issue planet. Remember that you'll want some dry land for your life to ascend to, and that water is a powerful greenhouse gas.

Then, when you've got some seas and precipitation going, just fire up some volcanoes for CO2, and that should get you some primitive life going.

Re:Sounds intelligently Designed (1)

symbolset (646467) | about 2 years ago | (#40657359)

A lot of little ones, or a few big ones. One remaining asteroid that we know of - 1 Ceres - has as much water on it as all the fresh water on Earth. There's quite a lot more water on Earth than we can see though - it's just mixed in with the rock, trapped in the mantle.

Re:Sounds intelligently Designed (0)

Anonymous Coward | about 2 years ago | (#40656839)

They went to Mars, Venus and Mercury was always too hot and small.

Mars water was blasted off and frozen under ground.
Earth water is stable.
Venus water is stupidly hot.

Nothing magic about it.

Re:Sounds intelligently Designed (1)

FitForTheSun (2651243) | about 2 years ago | (#40656915)

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 (3, Funny)

Black Parrot (19622) | about 2 years ago | (#40657023)

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.

Re:Sounds intelligently Designed (1)

lightknight (213164) | about 2 years ago | (#40659045)

Which, if true, makes his death a crime against humanity. A source of wine cheaper than water...;-)

Re:Sounds intelligently Designed (3, Informative)

amck (34780) | about 2 years ago | (#40657037)

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 (1)

PNutts (199112) | about 2 years ago | (#40657235)

Please be patient while we work on what you belive is a work of fiction conflicts with your work of fiction.

Actually, it is more religion than science. (-1)

Anonymous Coward | about 2 years ago | (#40657313)

Anytime someone (there is no such thing as "science", "science" doesn't come up with things, people called harry, dave, elmer, they come up with things) comes up with a notion that "something we can't explain" came from "far far away", it is RELIGION.

It is putting stock in a higher power, that the rest of the universe is more exotic and weird than where we are now.

What if we ARE in the weirdest part of the universe?

Where did the ice come from on the asteroids? Were they hit by little wet Earths?

I don't see the rationale for arguing about water first being seeded in conditions that are mutually exclusive from those that develop a planetary mass on a particular orbit, nor do I see any argument compelling for this, it is another "plan 9" scape-goat (to use a religious term) that says "anything unexplained happened really far away, a really long time ago".

Re:Actually, it is more religion than science. (1)

Anonymous Coward | about 2 years ago | (#40657801)

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 oversimplification, but it answers your questions. The water was out there, and not right here, because of the temperature gradient that was present when our solar system was young. The model explains where the water came from, too, but if you play the "and where did THAT come from" game you eventually get to the big bang. The model doesn't say much about what happened before the big bang because we have no means of gathering any data about such a period.

So, the reason you don't see the rationale is mainly because you haven't done your homework. You don't actually understand the model you are attacking, and you are unaware of the data and arguments in defense of that model. So, we would expect that you don't find the conclusions compelling. But, of course, if you bothered to learn the facts rather than just form opinions, you might find the reasons more convincing (provided you are basically intelligent, that is).

Also, your definition of religion seems a bit odd. The key differences between science and religion are:

1) Proponents of science base their claims on observations and evidence, whereas religious followers base their claims on ancient myths.
2) Scientific models are changed when new data come to light, whereas religions teachings just reject all contrary evidence as lies, no matter how compelling.

Whether or not something is said to have come from "far away" seems irrelevant.

Re:Sounds intelligently Designed (1)

marcello_dl (667940) | about 2 years ago | (#40657695)

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 creation are completely orthogonal.

Once you damn people realize this simple concept, I hope you start treating the evolution vs intelligent design debate as the one of purple vs. salty.

Remember, the media pushes sterile debates, they can get endless ink out of it if you're naive, they keep our attention off productive debates if you're a conspiracy nut.

The Weekend Genesis (1)

jovius (974690) | about 2 years ago | (#40657827)

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.

Re:Sounds intelligently Designed (1)

hemo_jr (1122113) | about 2 years ago | (#40658241)

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 crater in Greenland is the first direct evidence of the bombardment hitting Earth. Weathering and continental drift have made getting such direct evidence difficult.

Examination of isotope ratios in comparison to what is known for for various types of asteroid are somewhat inconclusive for a particular family being the exclusive donator to Earth's oceans. But, I stand by the estimation that the Hungaria family provided the major portion.

Uh oh (0)

Anonymous Coward | about 2 years ago | (#40656667)

This can't be good for Space Nutters. One of their main points of their religion is in doubt now. Coupled with the fact that the DSM-V now describes a general anxiety disorder that can very well cover Space Nuttery, looks like a cure is just around the corner.

Re:Uh oh (1)

binarylarry (1338699) | about 2 years ago | (#40656697)

I love Space Nutter Butters.

Re:Uh oh (0)

Anonymous Coward | about 2 years ago | (#40656955)

And where would you get them on Mars? It's a dead dry rock last I checked. Oh let me guess, you'll 3D print some on arrival in your private space yacht, right?

Re:Uh oh (1)

tragedy (27079) | about 2 years ago | (#40657171)

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.

Re:Uh oh (0)

Anonymous Coward | about 2 years ago | (#40657377)

No, the Space Nutter religion states that asteroids are coming here to destroy our species, when in reality they are just part of the normal process of the universe. Who are they to decide what happens to this part of the universe?

Re:Uh oh (2)

tragedy (27079) | about 2 years ago | (#40659031)

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 almost inevitable. It's possible that we might have sufficiently advanced terrestrial technology at that time to weather it, but our chances are even better if we have space capabilities. In other words, it's not a religious belief.

Also, what you say here still doesn't explain what the original comment has to do with The Fine Article despite the common theme of asteroid strikes. Why would narrowing down _which_ asteroids supplied most of Earth's water do anything to injure the idea that a massive comet or asteroid might cause another global extinction event in the future? You seem to be using some sort of faulty reasoning. Do you also think that because the ozone layer is a good thing that protects us that we should all make sure to breathe as much ozone as possible?

GOD DID IT !! (1)

Anonymous Coward | about 2 years ago | (#40656691)

That's the simplest explanation. You nerds and your crazy ideas !!

Re:GOD DID IT !! (1)

Brad1138 (590148) | about 2 years ago | (#40656805)

Wow, you'r right. Why do we spend all this time, effort and money investigating things when the answer is so obvious...

Re:GOD DID IT !! (0, Funny)

Anonymous Coward | about 2 years ago | (#40657563)

Wow, you'r right.

Wow. Just... wow.

Re:GOD DID IT !! (2)

Black Parrot (19622) | about 2 years ago | (#40657033)

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? (2)

cpu6502 (1960974) | about 2 years ago | (#40656727)

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.

Re:How did the water get on the asteroids? (0)

Anonymous Coward | about 2 years ago | (#40656863)

Your correlation is surface area?
fail.

Re:How did the water get on the asteroids? (1)

poly_pusher (1004145) | about 2 years ago | (#40656865)

I think the idea is that the water was always there. That is to say ever since the supernova that seeded us happened. In the case of the asteroids, just like their rocky material, the water would have been part of the mix that coalesced into asteroids. Asteroids are failed planets that didn't attain enough mass to become a planet. They are also relatively small so not much heat would have resulted from their forming. They never got hot enough to boil it off. It's such a strange thing to think of water as a rock-like material but as long as it isn't heated to it's melting point it seems to behave a lot like rock which we are seeing evidence of on Titan.

Re:How did the water get on the asteroids? (5, Informative)

MightyYar (622222) | about 2 years ago | (#40656889)

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]

Re:How did the water get on the asteroids? (1)

dissy (172727) | about 2 years ago | (#40657195)

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!

Re:How did the water get on the asteroids? (1)

fustakrakich (1673220) | about 2 years ago | (#40657283)

That is cool. I wonder how big a sphere all the humans would make. And then all the biomass.

Re:How did the water get on the asteroids? (0)

Anonymous Coward | about 2 years ago | (#40657447)

Something about that graphic looks wrong. That wouldn't be enough water to fill 1 ocean.

Yes, it would (5, Informative)

F69631 (2421974) | about 2 years ago | (#40657727)

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.

Re:How did the water get on the asteroids? (1)

marcosdumay (620877) | about 2 years ago | (#40656891)

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.

Re:How did the water get on the asteroids? (1)

symbolset (646467) | about 2 years ago | (#40657979)

Or some of it wasn't trapped by infall and then released by the Late Heavy Bombardment as large chunks of mantle were blasted into mist - which would have been my guess.

Re:How did the water get on the asteroids? (0)

Anonymous Coward | about 2 years ago | (#40657455)

The Earth is only 0.1% water by mass. Still a lot of asteroids, though, yes. But our observations suggest that there are quite a lot floating around the outer solar system.

The moon (2)

poly_pusher (1004145) | about 2 years ago | (#40656755)

If this is true then how much water does the moon have? It seems like that should be estimable and relevant to the future if space travel if we assume all the earths water came during the late heavy bombardment. It also could be a good way to test this theory. If concentrations of water on the moon don't correlate wouldn't that poke some holes in the theory?

Re:The moon (1)

Anonymous Coward | about 2 years ago | (#40656811)

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.

Re:The moon (1)

poly_pusher (1004145) | about 2 years ago | (#40656927)

But the moon is still one of the strongest pieces of evidence for the late heavy bombardment. They did form in very different environments but wouldn't they have a similar concentration of water if the water on earth arrived at the same time as our moon got heavily cratered? Earth certainly didn't get this water prior to the moon getting knocked of the earth. It was a swirling ball of magma that would not have held on to any water for quite a while after that event.

Re:The moon (3, Interesting)

tragedy (27079) | about 2 years ago | (#40657207)

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.

Re:The moon (0)

Anonymous Coward | about 2 years ago | (#40656843)

The argument is asteroids from the inner solar system versus asteroids from the outer solar system.

Re:The moon (1)

emagery (914122) | about 2 years ago | (#40656931)

not exactly... asteroids from the inner system have some water in them... but the bodies in the outer system are primarily NOT asteroids, but in stead are comets and kuipers. Mostly water as opposed to Mostly rock/metal... kind of a huge difference, really, when one is trying to punch its way through your atmosphere.

Re:The moon (1)

tragedy (27079) | about 2 years ago | (#40657231)

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.

Re:The moon (1)

wjcofkc (964165) | about 2 years ago | (#40656911)

By most modern estimates the moon contains more water than exists on the face of the earth. I will leave it to you to search slashdot for the relevant articles.

Re:The moon (1)

FitForTheSun (2651243) | about 2 years ago | (#40656929)

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.

Re:The moon (1)

Brain-Fu (1274756) | about 2 years ago | (#40657471)

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.

We need one more (0)

Anonymous Coward | about 2 years ago | (#40656845)

We need one more Asteroid when our wells start running dry

Asteroid impacts == good (0)

Anonymous Coward | about 2 years ago | (#40656895)

Wait, so asteroid impacts are good now?

Re:Asteroid impacts == good (1)

Brain-Fu (1274756) | about 2 years ago | (#40657499)

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.

not really surprised (1)

emagery (914122) | about 2 years ago | (#40656899)

I mean, look at what we see with other protostars forming out there; the compaction of gasses from nebulae... and with the building blocks of water being so extremely common out there (contrary to the plot of 'ice pirates') its only natural that water will condense into these protosystems as well... and water has a tendency to build up a static charge, which would probably influence its distribution, especially in 'warmer' parts of the forming system. I would resume that it would congregate easier closer in, and most of what is found in the outer system (oort and kuiper type structures) may be what was thrust out there by the 'ignition (for lack of a better term)' of the new star. It's all speculation, but based on observations.

So what's up with the deuterium? (0)

Anonymous Coward | about 2 years ago | (#40656919)

From TFA:

The amount of deuterium in celestial bodies' water ice sheds light on where the objects formed in the solar system's early days. In general, bodies that took shape farther from the sun have relatively higher concentrations of deuterium, researchers said.

IANAA (I Am Not An Astrophysicist), but that's interesting.

What's the mechanism by which this is presumed to be the case?

In lieu of an actual answer, I'll throw out a hypot^H^H^H^H^Hwild-ass-guesse: in a collapsing cloud initially composed of a mix of hydrogen and deuterium, the heavier deuterium will wind up sinking into the part of the cloud that becomes part of the star, leaving the parts of the cloud that were closest to the star (but which didn't fall into the star before it ignited) deuterium-depleted.

Re:So what's up with the deuterium? (2)

arisvega (1414195) | about 2 years ago | (#40657427)

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 are a hundred or a thousand times smaller than the envelope (few tens to a couple of hundred AU).

Here is some nice imaging [wikipedia.org] of an accretion disk.

How exactly all this happens is an active area of research. One of the things that give some insight on the stellar and planetary formation process is measuring relative isotopic ratios on things in space, and comparing them to terrestrial and Solar values. What Conel Alexander and company here have noticed here is that the D/H ratio of Earth's water is more similar to the one of some Carbonaceous Chondritic [wikipedia.org] meteoritic material than it is to some comets.

The Carbonaceous Chondrites are dated to be old. Not the first solids of the Solar System, but still among the first. They were also deemed to never have been parts of a larger body: they were never, say, part of an ancient planet, and then broke-off: they formed as rocks (condencing out of gas and dust) somewhere and at some time in the accretion disk, early. Or so the story goes.

I guess a ranting point can be that there is this theory of the Late Heavy Bombarment [wikipedia.org] : there are people in the community that believe the Late Heavy Bombardment was also the origin of Earth's and Mars' water oceans, that came from comets (which carry lots of water). But water in comets, as it is now, is different than the water of Earth's oceans in terms of its D/H ratio.

Re:So what's up with the deuterium? (1)

arisvega (1414195) | about 2 years ago | (#40657855)

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.

Just my own musings... (1, Insightful)

SternisheFan (2529412) | about 2 years ago | (#40657003)

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? Frozen water. Lots of iceballs with the 'seeds of life' in them. Since all life on earth is based on water, and water is not native to earth, all of our water came from 'out there'. So, if life sprouted on this planet, it stands to reason it's happened everywhere. Ergo, we most likely are not 'alone'.

Re:Just my own musings... (3, Insightful)

Black Parrot (19622) | about 2 years ago | (#40657053)

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.

Re:Just my own musings... (2)

SternisheFan (2529412) | about 2 years ago | (#40657111)

If you can create universes, you can pretty much deliver life any damn way you want to, I imagine. Who's gonna tell you no?

Re:Just my own musings... (1)

SternisheFan (2529412) | about 2 years ago | (#40657279)

I've recently heard about the theory of an 'intelligent universe', If it proves out one day to be true, think of the universe as one huge-ass computer that is "alive" & thinking. On a magnitude wa-a-a-y beyond human capacity. It's an interesting theory I heard on the Science channel's "Wormhole" program, the onwe narrated by Morgan Freeman. Heckuva good show.

Re:Just my own musings... (0)

Anonymous Coward | about 2 years ago | (#40659147)

If you can create universes, you don't need "delivery systems". You just speak your will into being.

Maybe not after the universe is already running. You've played with enough software to understand this.

Re:Just my own musings... (1)

sheetsda (230887) | about 2 years ago | (#40657417)

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.

Re:Just my own musings... (1)

SternisheFan (2529412) | about 2 years ago | (#40657725)

Those are both interesting reads, thanks. No need to apologize This is why I dig Slashdot, I'm always learning something new here.

Re:Just my own musings... (1)

Baloroth (2370816) | about 2 years ago | (#40657529)

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 develop, which means you end up with a massive quantity of it which is capable of adapting to any situation (in other words, if a billion species fail to adapt, you have several billion more waiting to try). But if the entire planet was high radiation (for example), such life may never be able to arise in the first place.

Can somebody please explain..... (1)

mark-t (151149) | about 2 years ago | (#40657009)

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?

Re:Can somebody please explain..... (1)

SternisheFan (2529412) | about 2 years ago | (#40657081)

When 1st forming, or 'accreating', the earth was way too hot, any water would be boiled away. Once it cooled enough, any bombardment of ice would collect over time into oceans. Yeah, we are talking a lot of ice hitting earth. If anyone has a better explanation, I'm open to it.

Re:Can somebody please explain..... (1)

mark-t (151149) | about 2 years ago | (#40657181)

Where would it boil away to, exactly? AFAIK, Earth's gravity is strong enough to hold onto water vapor without it getting into space.

Re:Can somebody please explain..... (1)

Anonymous Coward | about 2 years ago | (#40658249)

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 lighter and more able to escape. Not to mention, that which did wind up being part of the Early ball-of-clay would not have occasion to recombine into water, since it was too busy being cooked in the molten metals that now form the Earth's core. Even the hydrogen and oxygen atoms that did wind up in the modern crust would have, you know, dirt, between them, and hence would not form into water.

Re:Can somebody please explain..... (2)

The Snowman (116231) | about 2 years ago | (#40657091)

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?

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, the water boils and becomes vapor.

Being that I am not an astronomer or astrophysicist, I'm not going to conjecture what really happened: but the theory goes that since Earth was too hot, water must have been delivered to it later on. Since asteroids are small and were freezing cold while Earth was super-hot, the theory goes that asteroids bombarded Earth and delivered water.

What I don't get is why would it not be possible for the water to have boiled off the surface, but floated to the top of whatever primordial atmosphere the Earth had? Or if no atmosphere, just hang out near the surface until things cooled off?

From Wikipedia (0)

Anonymous Coward | about 2 years ago | (#40657237)

"The inner Solar System, the region of the Solar System inside 4 AU, was too warm for volatile molecules like water and methane to condense, so the planetesimals that formed there could only form from compounds with high melting points, such as metals (like iron, nickel, and aluminium) and rocky silicates. " --Formation of planets [wikipedia.org]

That took me like two minutes of searching to find. You could have found it in little more than double the amount of time it took you to type up your post.

Re:From Wikipedia (1)

mark-t (151149) | about 2 years ago | (#40657647)

Except that the single most common element on Earth is *NOT* a metal... it is Oxygen. and I know already what they say happened.... what I'm not finding is any explanation for why a planet with sufficient gravity keep all but the very lightest gasses from escaping could not have had lighter compounds forming there as well.

Re:From Wikipedia (0)

Anonymous Coward | about 2 years ago | (#40657911)

HEAT. The reason why water didn't form right on Earth when it was first forming was HEAT. The solar radiation was sufficient to blast apart any hydrogen from associated oxygen, resulting in NO water and gasses which were independently light enough to easily escape the weaker-than-now gravitational field of a still-smaller-than-now Earth.

Apparently, you don't know as much as you think you do, as Oxygen is only the most abundant element in the Earth's crust (the last-to-form part of the Earth). The core of the Earth is all heavy metals.

The answers are there. They are all derived from the best evidence of the moment, though, and subject to change if new evidence comes to light. So some of the answers might actually be wrong. But your specific attacks aren't pointing out any gaping holes in the model, just gaping holes in your comprehension thereof.

Time to paint a big bullseye on Venus (1)

SlovakWakko (1025878) | about 2 years ago | (#40657147)

That ball of acid and CO2 could really benefit from some H2O. So there's the new terraforming plan: paint a bullseye on Venus, and they'll come...

Re:Time to paint a big bullseye on Venus (1)

spire3661 (1038968) | about 2 years ago | (#40657691)

It always shocks me how casual people are with the idea of completely altering ANOTHER planet.

Obligatory post (0)

Xtifr (1323) | about 2 years ago | (#40657199)

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. :)

Re:Obligatory post (1)

SternisheFan (2529412) | about 2 years ago | (#40657381)

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. :)

Because it's Slow-News-Day Sunday on Slashdot. **holds nose for dunking**

2/3 of our planet came from asteroids? (0)

Anonymous Coward | about 2 years ago | (#40657431)

What? Do these people even THINK about the stupid theories they come up with?

Re:2/3 of our planet came from asteroids? (0)

Anonymous Coward | about 2 years ago | (#40657807)

re: 2/3 of our planet came from asteroids? actually, more like 3/3rds of the planet came from asteroids.

Desert world (1)

kstahmer (134975) | about 2 years ago | (#40657487)

We call Earth a water planet. It seems preposterous that a bunch of rocks could bring in enough water to fill Earth’s lakes, rivers and oceans.

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. (1)

Khyber (864651) | about 2 years ago | (#40658007)

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.

Re:It originated from our fucking sun, morons. (1)

Brain-Fu (1274756) | about 2 years ago | (#40658335)

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 that we call "asteroids." Some of those then got drawn back in by the Sun's gravity, and crashed into the Earth.

So....asteroids delivered water to the Earth, exactly as the article says. And the water was baked up and shot out from our own Sun before that. Though some of the water may have drifted in to our outer solar system from other solar systems after they went through the same process, too.

also from the core (1)

shpoffo (114124) | about 2 years ago | (#40658317)

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.....

Biblical flood (0)

Anonymous Coward | about 2 years ago | (#40658501)

And the xistians will use this as evidence of the biblical flood.

Android crashes???? (0)

Anonymous Coward | about 2 years ago | (#40659023)

Oh, asteroid. Yeah, that makes a bit more sense.

oh hey (0)

Anonymous Coward | about 2 years ago | (#40659041)

My unprovable theory about what happened billions of years ago can beat up your unprovable theory about what happened billions of years ago!

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