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Comets Probably Seeded Earth's Nitrogen Atmosphere
KentuckyFC writes "One of the biggest puzzles of astrobiology is the origin of the Earth's oceans and atmosphere. One favored theory is that our water is the leftovers from a bombardment of comets early in Earth's history. But the ratio of hydrogen and deuterium in the oceans doesn't match the ratio in the four comets measured so far (Halley's, Hyakutake, Hale-Bopp and C/2002 T7 LINEAR). Now a new analysis of the ratio of nitrogen-14 and 15 isotopes in these comets and on Earth places new limits on how much of our environment could have come from comets. On the one hand, the astronomers who did the work say that no more than a few percent of Earth's water could have come from comets. But on the other, they say that the ratio of nitrogen isotopes in these comets almost exactly matches the ratio in Earth's atmosphere. That suggests that while Earth's oceans must have come from somewhere else, Earth's early atmosphere was probably seeded by comets."
Space.com brings word of a team using new evidence is suggesting that the mysterious 1908 event in Tunguska was a comet despite a team two years ago arguing it was an asteroid. The comet theory does explain the odd phenomenon of the night skies being lit up for several nights following the event all across Europe--about 3,000 miles away. Researchers believe this points to a comet because when the space shuttles launched today pass through the atmosphere they cause or improve the formation of noctilucent clouds. These clouds are so high up (55 miles) they are only made of ice particles and they are only visible at night which gives researchers reason to draw the conclusion that the 300 metric tons of water vapor that the shuttle pumps into the Earth's thermosphere must likely indicate that the thing that hit was loaded with water or ice. This would make it a comet and not an asteroid. This--of course--raises new upper-atmosphere physics problems for the Tunguska event but explains the strange phenomenon over the skies of the world following it. You may remember analysis of Lake Cheko last year in an effort to better understand what happened.
Well, if every comet that hit earth dropped off a little bit of water--even in the form of noctilucent clouds ... it'd take a while but is it really so far fetch to think that ultimately all our water and atmosphere are extra-terrestrial? Probably unlikely but over a long enough time, who knows?
My work here is dung.
Nitrogen came from comets, and methane came from Uranus.
The article notes that the ratio of the nitrogen isotopes matches what is in the earths atmosphere. It seems to me, that just makes it possible that the comets are a significant source of the nitrogen on Earth. It is also possible that the nitrogen in the comets and in the atmosphere came from a common source.
Duh, it reproduced once it arrived on Earh.
In addition to creating an atmosphere on earth, comets may also have seeded life.
Comets Probably Seeded Earth's Nitrogen Atmosphere
So we've been breathing space spooge all along?
Well THAT explains a lot...
[End Of Line]
Everyone knows nitrogen is here because of the Holy Sauce dripped from His Noodly Appendage.
Although comets may have initiated seeding of life and the foundry of everything from water to minerals .. there has been proof that water is abundant in space and maybe have just been absorbed into the atmosphere on earth and generated that way, over time rain would have brought the water molecules to the surface.
http://www.space.com/scienceastronomy/astronomy/milkyway_water_010412.html
It's not a typo if you understood the meaning!
Astronomers renamed that planet in 2020 to stop that stupid joke once and for all.
Oh. What's it called now?
Urectum
Conscience is the inner voice which warns us that someone may be looking.
My guess is that earth started out as a (not -so-giant?) gas giant and bled of most of it's original hydrogen. If that's even vaguely true, then there's little likelihood that the isotope mix would be anywhere near what's in comets.
I'm guessing that the deuterium mix is much higher than in comets (because deuterium, being heavier than hydrogen, is less likely to bleed off).
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just about anything in the universe, and specifically various aspects of this planet, is becoming more like numerology than anything else. Case in point:
But on the other, they say that the ratio of nitrogen isotopes in these comets almost exactly matches the ratio in Earth's atmosphere. That suggests that while Earth's oceans must have come from somewhere else, Earth's early atmosphere was probably seeded by comet.
Any pattern they find seems to make scientists believe something is true, no matter how improbable. Scientists are only seeing what they want to see in this data. Despite this method of guessing based on simply "interesting patterns" and hoping they are right, these very same people consider taking on faith what the Holy Bible says about the origins of the world as being ludicrous. Ahhh, nothing like the smell of hypocrisy in the early morning hours. Flame on for bucking the *insertGroupNamehere* agenda.
this nation, under God, shall have a new birth of freedom. -- Lincoln, Gettysburg Address
The theory of comets as a source of water was also published in 1990, by Louis A. Frank.
Not exactly your average crack-pot scientists, Frank was the designer of something like 13 payloads on various launch vehicles in the 80s and 90s.
Frank posits that that small comets still hit the moon and earth almost daily, delivering water virtually every day. These small comets are more like fluffy snowballs, and are small enough not to have much if any radar signature, but their effects upon impact with the atmosphere are visible from above.
http://en.wikipedia.org/wiki/The_Big_Splash_(book)
Excerpt from The Big Splash
by Louis A. Frank with Patrick Huyghe
Published by Birch Lane Press, 1990.
ISBN 1-55972-033-6
http://smallcomets.physics.uiowa.edu/blackspot.html
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No, it isn't a mystery.... Gen 1:1 In the beginning...
That's the Cliff's Notes abstract. For the expanded version, start with the Big Bang and use physics.
God is the name I give to the Universe and all her natural laws.
Science is my prayer. I keep my logical integrity intact by understanding that the converse is not also true.
Do not mock my vision of impractical footwear
If those passages aren't a mystery to you then I say you need to go back to elementary school and learn how to read critically. Who is this God character? How did he create the heaven and the earth from something without form, out of a void? There are obviously some details missing and I demand a refund for this explanation of the universe you have sold to humanity.
I was under the impression that the Earth's water precipitated out of the original accretion disc as the early earth cooled. That is, everything accreted, and then as the molten rock and surrounding gases cooled to form a sold surface, the water that became the Earth's oceans and such also cooled and condensed, and basically rained down on the planet over time.
Has there been some reason to doubt this? i.e. evidence that refutes this hypothesis?
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
It's easy (unless you're a fundie) to understand where the heavier elements and such come from, since they melt at high temperatures.
But water and the "stuff" that are gases at STP are volatile. So... what kept them "near" the earth while it was very hot (way past the boiling point of waster) and small and accreting? There wasn't enough of a magnetosphere to protect any atmosphere.
Could it be that H2O, N2 and O2 were created from the decomposition of very hot rocks?
"I don't know, therefore Aliens" Wafflebox1
I can easily picture the Flying Spaghetti Monster lobbing comets around ...
This is a rapidly evolving field and I don't pretend to have more than a very casual reader's knowledge - but think of it like this. The Earth is, in cosmic terms, a small planet. Its water layer is a minute fraction of its mass. In terms of the solar system as a whole, the percentage of the available water on Earth is extremely small.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Let's see. first of all, it's entirely possible that some guy's personal world flooded, wiping out his neugbours and that he and his livestock escaped becase he happened to have a boat. Indeed, statistically, it must have happened often. I think the Epic of Gilgamesh has a somewhat similar event.
The solar wind is hydrogen nuclei, and going much faster than 33000 mph, but it's VERY VERY thin. I doubt the total amount impacting on the Earth's magnetic field in a year would be enough to raise sea levels a millimeter. Also, the same impacts will knock a certain amount of hydrogen off water molecules in the upper atmosphere and kick them off into space, so we lose as well as gaining.
Dude, your passage doesn't actually say anything about where the ocean and atmosphere came from. It just claims that God pushed some water around a bit.
If you're going to vest your credibility in a mythological text, you should at least read it carefully.
Sheesh, evil *and* a jerk. -- Jade
what happened to the dept tag?
Media that can be recorded and distributed can be recorded and distributed.
-kfg
I find these stories kind of unfulfilling. No matter how far we get back in nature's cause and effect, I'm still left thinking 'what came before that'. When scientists finally discover the root of all creation, I'll still be thinking the same thing.
"In the absence of the ability to establish the attribute of truth they tried to establish the noble attributes."
No, it isn't a mystery.... Gen 1:1 In the beginning God created the heaven and the earth. Gen 1:2 And the earth... and God saw that it was good.
Yeah, all right, what really happened? Tell the truth.
Gold? That would be from a supernova.
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to believe in some of these theories....
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Thanks to the RIAA, I buy them used...
This is a comparison, not a correlation.
No kidding!!! What do you say at this point?
Well, I'm glad you've got it all figured out, everybody in planetary formation research can go home now.
No kidding!!! What do you say at this point?
Then Eve went into the orchard, and Satan talked her into trying a bite out of the tree of life. And then she talked Adam into a bite.
Then they fucked, and Eve went down to the river to bathe.
God saw Adam cowering behind a bush and said "WTF???" And Adam said "er, uh, um" and God said "Damn it, you ate that apple, didn't you? Then you fucked her, didn't you?"
And Adam said, Uh, yes sir, I'm sorry..."
And God said "Ok, whered the bitch go?"
And Adam said "she's down by the river washing up."
And God said "Oh shit, I'll never get the smell out of those fish!"
Free Martian Whores!
There's a great many people trying to make God go away. Kinda sad, really. No one tries to make Buddah go away, or discount Ra, or dispute Karma.
Just to point out, everyone who has ever taken the moral high ground with me based on religion, or anyone who has ever tried to shove religion down my throat, or sell it to me from my doorstep, have all worshiped the Christian god. I'm counting Muslims among these people as well, Islam is basically a breakaway Christian sect. I've never seen a Buddhist running around with an AK looking to kill anyone who doesn't believe in Buddha, and I haven't heard of any Egyptian campaigns, or crusades if you will, to spread their religion around the world. People who have a negative reaction towards the Christian god have that reaction probably because it has been shoved down their throat from day 1 with people claiming that if you don't believe the same thing you're automatically wrong about whatever you're arguing.
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
they say that the ratio of nitrogen isotopes in these comets almost exactly matches the ratio in Earth's atmosphere. That suggests that while Earth's oceans must have come from somewhere else, Earth's early atmosphere was probably seeded by comets.
Or the nitrogen in the comets and the nitrogen in the Earth's atmosphere had a common origin which seems much more likely, the story title notwithstanding.
I keep going over the proof for Noah's flood. It's not as far-flung as it sounds if you actually RTFM. It calls for a number of animals that would fit in a rowboat- it doesn't have to be millions. And it doesn't have to be a full world, either: Rome 'taxed the world' and I'm certain they didn't get New Jersey.
What? Considering there are thousands of species of mammals, birds, amphibians and reptiles each. Plus 100,000s of species of plants and millions of species of insects it must be quite a large row boat. No they could not have evolved suddenly in the last few thousand years, into the multitude we see today.
So here's the question.
What *actually* happens when the poles reverse and the Van Allen (etc) belts come down for a short time? The solar wind, largely H3 I'm told, touches an oxygen-covered surface at 33,000mph. So hot hydrogen..on oxygen...rain?
Well the Van Allen belts will dissipate presumably dumping some charged particles in the atmosphere. The reduced magnetic field will allow more solar wind and cosmic rays to hit the atmosphere. But considering there have been many such reversals over time and life has survived fine it's probably not that bad. Regarding rain well I don't know but as the last reversal was 780,000 years ago I doubt it was ever recorded. Homo sapiens are believed to have originated 200,000 years ago.
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I don't understand
Uh, huh. Well if you notice that the four inner planets are rocky and most are devoid of water. While the outer planets are made of gas and bigger maybe the material that formed the solar system was not evenly spread. The top reason for this is the sun is hot! Read an encyclopaedia.
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I hate to derail the discussion, but you did ask for it. People don't try to make Buddha go away because Buddha never claimed to be a god. He always maintained that he was just a man. So why try to make him go away? People have issues with Christianity because they see things like the Pope saying condoms don't prevent AIDS, ministers railing against gay people, and thousands upon thousands of Christians making a mockery of marriage by getting divorced all over the place. People are just fed up with hypocrisy and such obvious hatred. And, yes, the Bible has been correct about a few things. But it's been sooo wrong on soooo many more things, it's pointless to try to use it as a source of fact, as you might as well make the truth up - you've got just as much chance of being right. And you might want to read this list of crucified saviours, some of whom are claimed to have ascended to heaven, with just as much evidence for it as for Jesus.
This is only a puzzle if you come from a particular worldview.
It's so difficult that it isn't practical. As another poster pointed out you can create gold from wood using high-energy equipment, but the energy invested would be worth more than the gold produced and therefore there are limitations on what you can and can't do. So, while strictly speaking it is possible, there are economic considerations.
By the time that you've got your rocks molten, their water, CO2 and ammonia (nitrogen in it's most-likely protoplanetary form) would have pretty-much fucked right off. At the time that the Moon was formed (giant impact hypothesis, still the best one running), much of the depth of the mantle was temporarily ejected into low proto-Earth orbit, and at sufficient temperatures that significant amounts of such volatile ions as sodium were also lost from the material that accreted into orbit to form the Moon. This can be quite clearly seen in the composition of lunar rock samples - noticeably sodium deficient and as dry as a bone.
In planetary science, it is uncontroversial that no-matter how wet the Earth was when it formed, it was fairly well dried out by the time the Moon had formed. Consequently, the Earth then had to acquire it's volatile load (water, nitrogen-as-ammonia, carbon dioxide) after the Giant Impact. Since the Giant Impact would have necessarily (?? well, most likely) involved the mutual accretion of the two largest bodies remaining in the Earth's orbital range form the Sun, there wouldn't have been much left to accrete after that. So, most of the Earth's volatiles must have come form somewhere else.
That's one line of "geologically-based" thinking that leads to the Earth's non-volatile and volatile components having different origins. There's a simpler, astrophysically-based line of thinking that leads to the same conclusion from different premises : many meteorites contain a class of devitrified formerly-glassy chondrules called CAIs (Calcium-Aluminium[-rich] Inclusions) which give some of the oldest ages in the solar system (from our inventory of samples, but these are well and diversely sampled from stony meteorites, and give a coherent thermal history) ; the de-vitrified glassy textures tell that they were metamorphosed from a glass at temperatures consonant with their surrounding mineralogies in their various meteorites, and the fact that they were previously glasses tells us that they had got hot enough to melt and then cooled fast enough to become glassy. That tells us something about the thermal history of the early times of the solar proto-planetary disc. Which in turn tells us something about the early heating history of the sun. Which ties in with our understanding of nuclear fusion, which is good enough to make bombs if not power plants. And the whole lot boils down to (pun not intended) ... in the early accretion of the Earth, and most meteorites, anywhere much Sunwards of the asteroid belt was too hot for water-ice (let alone ammonia-ice or carbon-dioxide-ice) to be stable.
The early Earth (and Mercury, Venus and to a lesser degree Mars) was pretty dry when it accreted. All got significant amounts of their volatile inventory later in the formation of the Solar System, after the "rocky" planets had essentially completed forming.
I am not aware (IANA Planetary Scientist, but I am a geologist by trade, currently steering a horizontal oil well) if the accumulation of water ice evaporated from the "rocky planets" region onto the proto-Jupiter is currently "fingered" as what tipped that one into becoming big enough to start to accrete hydrogen directly. But I am pretty sure that it has been suggested. The modelling is, as I think I've hinted, complex.
But the PS story is clear : the terrestrial planets got most of their volatiles AFTER they had effectively finished accreting.
Hmm, have we got the well sidetracked yet? Oh dear. Oh very dear.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"