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Where did all the Earths water come from?

  1. Jun 23, 2011 #1
    I have heard some people mention it may have came from the theoretical Oort Cloud or comets, ect...

    I'm wondering why a common guess as to where it comes from is from isn't within a lighting storm itself.

    Hydrogen and Oxygen are pretty much abundant in a lightning storm. The first crack of lightning is sometimes accompanied by a downpour, and lightning has recently been discovered to give off anti-matter signatures.

    I am no physicist, but isn't anti-matter a signal that matter has been produced?

    Where did all the Earths water come from and why is not an obvious thing to think the water could be manufactured in the clouds? Just some of it, not all of it, not the clouds themselves which are formed by evaporation, but perhaps lightning contributes to the total mass of a storms rain through matter production?
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  3. Jun 24, 2011 #2


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    A study, accepted for publication in the journal Astronomy & Astrophysics, says ESA’s Herschel Space Observatory has spotted a young sun-like star 750 light-years from Earth that is shooting water from its poles at about 124,000 miles per hour.

    Neptune and Uranus appear to be water planets. If it is typical for distant proto-stars to undergo a period of water ejection, then it is very logical to think that Earth's water came from the sun.


    Respectfully submitted,
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  4. Jun 24, 2011 #3


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    Pretty much all of the current matter that makes up everything in the solar system, including Earth, was already in the nebula that the solar system formed from.

    While Oxygen accounts for about 21% of earths atmosphere, free Hydrogen is pretty much nonexistent. Hydrogen is VERY reactive and will form compounds with almost anything. The only way I could see Hydrogen existing during a lightning storm would probably be due to the lightning splitting the Oxygen and Hydrogen in water apart.

    The antimatter produced from lighting is, at best, simply positrons, the anti-particle of an electron. It is most definitely not forming protons and neutrons. That requires far more energy. And even if it did these protons and neutrons would have to form into specific combinations to create Hydrogen and Oxygen which would then have to form water. Needless to say, this isn't happening.
  5. Jun 24, 2011 #4


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    As Drakkith points out, H is extremely reactive, especially with O.

    I'm afraid, by the time the Earth had an atmo at all, there was not much in the way of free hydrogen.
  6. Jun 25, 2011 #5
    Isn't this a rather circular argument?

    Evaporation of what?
  7. Jun 25, 2011 #6
    Greenwood et al. (2011) show a distinct overlap between the hydrogen/deuterium ratios of Earth's water and carbonaceous chondrites, so that is a plausible and likely source.
  8. Jun 26, 2011 #7
    Uh, the Oxygen came out of a red-giant or supernova, found its way into the gas & dust cloud which collapsed to form our solar system. The hydrogen and its deuterium isotope are primordial...
  9. Jun 26, 2011 #8


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    As dark society points out, it is entirely possible that Earth's water did not come when Earth coalesced from the gas cloud. There is much speculation that it was brought later in the form of meteors - as we as comets.

    While yes, technically those meteors and comets were part of the primordial dust and gas cloud, the intervening step of meteroic bombardment is an important distinction.
  10. Jun 28, 2011 #9
    Indeed! As Robert (2011) explains, there's a significant distribution in D/H ratios between various planetary bodies, including the Earth and Moon:


    Perhaps Nik would like to do some reading:

    Greenwood, J.P., Itoh, S., Sakamoto, N., Warren, P., Taylor, L., and Yurimoto, H., 2011: Hydrogen isotope ratios in lunar rocks indicate delivery of cometary water to the Moon. Nature Geoscience, vol. 4, p. 87-92.

    Robert, F., 2011: Planetary science: A distinct source for lunar water? Nature Geoscience, vol. 4, p. 74-75.
  11. Jul 13, 2011 #10
    Well this interesting. Free Hydrogen.

    So if I ask where the earths Hydrogen came from, can it be traced to either the condrite or kupier belt theory?

    I'm inclined to make a loose connection between the abundance of oxygen in the earths crust with the oxygen in the air. Correct? I mean over a few billion years, at least some of the atmosphere is blowing off into space. It has to be replenishing by a means not associated with accretion at the very least.

    So this makes me wonder, why Earth has the MOST water of any planet. Jupiter in theory is a huge gravitational shield pulling most meteorites towards it, is it not? So, if there were heavy bombardments, it surely must have been a significant amount. And, should any of the atmosphere be lost to space, perhaps the earths past was significantly more water abundant than now?

    So... why does a lack of FREE Hydrogen prevent Anti-Matter signatures from what appear to be the most powerful and intensely concentrated natural, and regularly occurring energy spikes on the planet, from combining hydrogen and oxygen to create H20?

    What is it specifically about the hydrogen on earth which makes it non-compatible with water.

    I am asking because I would like to learn more. I am not familiar with the concepts of FREE hydrogen and non-free hydrogen and specifically I am having a really difficult time wrapping my head around the significance of the antimatter signatures.


    My mistake... Free Hydrogen is just slang for there being a general lack of pure hydrogen. I think I misunderstood just how much hydrogen is in the atmosphere.

    Still can't figure out the whole anti-matter signature significance...

    Okay, wait a second... the exosphere is indeed abundant with hydrogen and the recently modern view of lighting is that is it massive and extends far past the atmosphere into the exosphere. So could that not be a source for the hydrogen needed to bond with oxygen to form water?
    Last edited: Jul 13, 2011
  12. Jul 13, 2011 #11


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    Please study this NASA article on gamma ray/antimatter production from clouds, and play the little video.http://www.nasa.gov/mission_pages/GLAST/news/fermi-thunderstorms.html

    It will be seen that:
    1) Powerful electric fields in clouds emit electrons upward near the speed of light.
    2) When these electrons encounter an atom, gamma rays are emitted. This happens maybe only 500 times/day.
    3) When gamma ray photons graze an atom, a pair of particles are created, one a normal electron, another the antimatter positron.

    This process seemingly has nothing to do with creating more water.

    Gushes of rain following lightning have been explained more conventionally. This has to do with large channels created around lightning strokes into which quantities of charged water droplets are drawn, if I recall correctly. (My copy of Uman is out on loan.)

    I hope this goes some way towards answering some of your questions.

    Respectfully submitted,
  13. Jul 13, 2011 #12


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    I have always wondered if this phenomenon were merely my imagination - a flash of lightning, crack of thunder, then an dramatic increase in rainfall for a few seconds.
  14. Jul 13, 2011 #13


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    Seemingly simple, ordinary clouds are truly an awesome work of nature, in my humble opinion, Dave.

    That common water droplets, against expectation, should coalesce, separate charge, self-assemble into particle accelerators and ultimately create particle beams, gamma rays and the antimatter we normally associate with stellar or nuclear events is nothing short of mind-boggling. To me, the nearby clouds are just as interesting as the distant stars.

  15. Jul 13, 2011 #14


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    Hydrogen was the primary element in the nebula that collapsed for form the solar system. That is where it came from. We have so little of it compared to the Sun or Jupiter and the gas giants because most of it formed the sun, and supposedly because the solar wind from the young proto-sun might have blown the lightest elements away from us. Enough remained to form Water and other molecules in the earth though.

    The oxygen molecule O2 is almost exclusively produced by plants. The atmosphere of early Earth was much more like that of Venus or Mars compared to normal day Earth. If any of our atmosphere is being blown off into space it is a very very small amount. Heavier elements like Oxygen, Nitrogen, and most molecules are too massive to be blown away by the solar wind in large amounts.
    Earth may have the most visible water of all the planets, but there's no telling how much might be in the gas giants under their outer atmosphere. Even if Jupiter has a small fraction of a percent of water composing it, it could be MORE than all the water on the earth. However I really don't know, so don't take that as a fact.
    I don't know what you mean by this.

    Free hydrogen just means hydrogen in the form of H2 or H1. H2 being composed of 2 hydrogen atoms and H1 is simply a lone hydrogen atom.

    Water is already composed of 2 hydrogen atoms bound to 1 oxygen atom. Further hydrogen atoms can do no more.

    If it is abundant with hydrogen, it isn't in sufficient amounts to form appreciable amounts of water. The exosphere's density is very very low.
  16. Jul 14, 2011 #15
    It is a cycle. Evaporation of water then clouds and then again clouds convert into water.

    air charter
  17. Jul 14, 2011 #16


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    Yes, but that isn't really what we are discussing here.
  18. Jul 16, 2011 #17
    Is this what is meant by Atomic Hydrogen and Molecular Hydrogen?

    If so... Hydrogen of this type is said to reside in the heterosphere. Which according to this article is right around 100 km high.



    In that general area Sprite lighting occurs. I am not a chemist but just searching around regarding what would be required to combine Hydrogen and Oxygen to create water, it mentioned that all that would be needed is some energy.

    From the following article:



    What doesn't fit in or make this a plausible possibility that perhaps Red Sprite and AntiMatter signatures might be evidence that water is being manufactered.

    Maybe perhaps rain that falls from the sky is never pure enough? Or perhaps it is not the right kind of Hydrogen? Or perhaps maybe the hydrogen is too far away from the lightning? These last few questions are more like rhetorical questions, than anything, I am just asking because I am trying to learn more and they are poor questions I am not really expecting an answer because I am asking too many at once.

    To suspend disbelief, if water was manufactured, and it was done in the heterosphere, would the gravity at that altitude have a strong enough pull to form rain drops, or would it just disperse as mist or something along that line? Perhaps it would have to be formed in the stratosphere and no higher for water to form rain droplets and fall back to earth?


    Looking around, it seems that clouds can form upto 100KM in the atmosphere. The source of water vapour is poorly understood.


    I have also found a video which mentions the aurora will penetrate into the atmosphere upto 50km above the surface of the earth. It says at about 6 and half minutes in that upto 1 MeV electron penetrates through the mesosphere to the top of the stratosphere.


    In all seriousness, Is 1 MeV electrons enough spark or energy to make H20 out of hydrogen and oxygen? And... if it were enough energy, would it give off an antimatter signature?


    Looking around, this is a really good video of sprite lighting, there are mentions that sprite lightning is associated with significant lightning strikes bound for earth in thunderclouds. In the video it shows altitude. They seem to be quite massive no matter how short lived they are, if anything their short duration should be a good indication of how efficient and powerful they are, right? They seem to start at the higher altitude which is right around the area that elemental hydrogen and atomic hydrogen should be in reasonable supply. Is it enough supply?

    It's a fairly awesome video, especially towards the end where one is said to re-ignite. Re-ignition of the sprite might be behavior which it not found in earth bound lightning, right? I was under the impression that lightning never strikes twice in the same spot but I am ready to dismiss that as urban legend. However earth bound lightning is following the path of least resistance, and potentially, so are these sprites, but what would make one follow the same path, or reuse some of the same path twice?

    In any event, re-ignition, from my perspective anyways is an indication that there is conductive agent which is burning up or acting as a conductor for the flow of energy. Would Oxygen and Hydrogen be a more likely conductor than lets say, nitrogen or another atmospheric element? If so, is there enough energy in those sprites to create water?
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  19. Jul 17, 2011 #18


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    Per here: http://en.wikipedia.org/wiki/Atmosphere_of_Earth
    The amount of Hydrogen in the atmosphere averages out to be 0.55 ppm by volume. That is an extremely low amount at 0.000055%.

    Above the homosphere, which is where the heterosphere starts, the different gases aren't mixed together very much due to their different molecular masses. Hydrogen doesn't with Oxygen much because of this.

    To my knowledge, the chemical reaction between Hydrogen and Oxygen does NOT create antimatter. There isn't anywhere close to enough energy released to create a positron.

    What? Have you ever watched any source of water evaporate? That is a direct source of water vapor into the atmosphere. This is constantly happening around any body of water. And the earth is covered in water. Hence there is a lot of water vapor in the atmosphere.
  20. Jul 17, 2011 #19
    Yes... and I looked at cumulus clouds, they seems to hit a max peak around 20 km or so, right where the troposphere ends.

    The higher altitude clouds, are really high up there. Maybe the Sprites lightning which in all honesty is rather amazing, creates just a little mist and it hovers right around where the cone forms at around 90km to 100km?

    Watching the video of the sprites, and I know it is bad measure to assume what is happening based on what my eyes are seeing, but it almost looks like a charge forms at the 100KM mark first, where the hydrogen is condensed, heated to a temperature exceeding it's bounding altitudes, then strikes down 80KM to the surface of the troposphere.

    What are the chances that it is carrying, and fusing hydrogen on it's way down, throwing water on the clouds? It almost looks like it is thrusting material down when it strikes too.
  21. Jul 17, 2011 #20


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    Fusing hydrogen? Pretty much not happening. Lightning doesn't reach anywhere near enough of a temperature for that to happen. I don't know why you keep insisting that this lightning is creating water. It is not. It is only transferring current from one area to another, not whole molecules.

    Cumulus clouds are not the only location of water vapor in the atmosphere. There is ALWAYS a small amount of water vapor in the atmosphere almost anywhere you go.
  22. Jul 17, 2011 #21
    I am not insisting... I am just sort of asking whether it is probable... what is the temperature requirement to fuse hydrogen and oxygen together?

    The wiki claims that atmospheric lightning can fuse silica into glass.

    "temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass"


    That is bolt lightning though, not sprite lightning. Sprite lighting is said to be much cooler, so perhaps you are right.


    I am just sort of questioning it, mainly because they might be associated with gamma ray bursts or anti matter signatures. Which I really have no idea what the circumstances or requirements are to make. My guess though, considering they might be associated with galactic explosions, is that to create them it might require a lot of heat. It's nothing counter intuitive, this line of thinking, is it?

    I just watched a documentary where they mentioned they were trying to prove that cosmic rays could act as the bonding agent needed for clouds to condense. Maybe that is all it takes is some accretion at the 100KM altitude to cause moisture to condense?

    So if the current is following the path of least resistance, and that path is different everytime, I would guess that after lightning strikes the path it follows makes it less conductive and more resistant to another possible lightning strike, correct?

    Maybe the re-ignition of the Sprite is an indication that it is following a different type of path? Perhaps it is following a path which is chemically conductive? perhaps nitrogen is a better conducing agent rather than oxygen?


    Okay... so what if the atmosphere is so thin where these sprites are occurring that heat cannot generate in a traditional sense, and it has to escape by another means? Is that a possibility? Would that explain why there is such a large amount of energy, enough to create Gamma ray flashes, or anti-matter signatures. Perhaps the radically different environment explains whey they could exist without causing a loud thunder clap?

    I have seen physics demonstrations that represent heat as molecules exciting and basically bumping around into each other more frantically. Perhaps the atmosphere is not dense enough to do this where the sprite occurs? If that is the case, would the lack of atmosphere or "heat" prevent any sort of fusion happening? Or maybe it is the perfect environment for "cold fusion"?

    I know that was a big science issue a while back, that's why I use the word "cold fusion" lightly.
    Last edited: Jul 17, 2011
  23. Jul 17, 2011 #22


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    Nuclear Fusion is in no way related to either of those. Hydrogen and Oxygen don't "fuse" together, they form a chemical bond with each other. The fusing of silica into glass just means that it gets heated enough to melt silica.

    I'd say it isn't counter intuitive or intuitive. It is simply that you are asking questions, getting answers, and then picking at random facts about 10 different subjects that seems to you to make this possible and asking more questions using those as guides. Instead, I would recommend learning what antimatter is, how it is created, what Nuclear Fusion is, etc. Just the basics.

    That might be plausible, I really don't know.
    No, the effect of lightning is at first preceded by a breakdown of the gas, aka Ionization, between the cloud and the target, either the ground or another cloud. After the strike the gas recombines and ceases to be ionized. Nothing about the path would cause it to become less conductive than it initially was. I don't know enough about sprite lightning to really speak on it, but the concept is similar.

    How do you know they don't cause a thunder clap? I've seen plenty of lightning in a storm that caused no thunder. Besides, the distance between the sprites and the ground along with the low density of the air probably doesn't allow a sound wave to reach us audibly.

    Fusion is not happening at all. Nor is cold fusion, as it doesn't exist in form the commonly used term refers to.
  24. Jul 17, 2011 #23
    I'm not particle physicist, but I thought fusion was a technical term for the particles surrounding the nucleus of an atom to bond with another. Or to split from it's parent molecule creating new type of material. I am not really fluent with all that stuff, it sort of eludes me once the whole plum pudding model is proven to be wrong. I just don't understand how they figure the weak and strong nuclear forces or what not, and for that matter, I just have no real concept of the difference between a chemical bond and nuclear fission or fusion. They are both chemical reactions the way I see it.

    I am asking to learn. Not to magically make something happen that otherwise would not be happening. I am not a magician.

    I am just reading and regurgitating what I find on the web. I don't know for certain if anything people put on the web is accurate.

    So could hydrogen and oxygen chemically bond without a fusion event, or a massive heat requirement? Maybe it just needs a little bit of heat? In a lab... not the sky...

    In any event. How do Red Sprites create anti-matter signatures? I thought anti-matter was an indirect observation of matter production. Gamma Rays being the result of two atoms colliding and forming matter, like fusion.

    The only thing I know about Gamma Rays and how they are produced is from reading about pair production... which is a form of intense energy forming matter. Maybe the scale of thinking on that is wrong, maybe that is sub-atomic, when really the only requirement is some sort of chemical requirement?

    See? Pair production, Gamma Rays - http://en.wikipedia.org/wiki/Gamma-ray_generation

    On the list is fusion too... so I am just wondering why lightning produces them as well... maybe I have concepts mixed up... I really don't know...
    Last edited: Jul 17, 2011
  25. Jul 17, 2011 #24


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    Well, if you really wish to discuss science, then it is best that you learn! Wikipedia is a good place to start. Look up Nuclear Fusion, Nuclear Fission, Chemical Bond.

    Hydrogen and Oxygen need very little heat to get them to bond. It is not fusion at all.

    I have no idea. I don't know that it is happening at all.

    Gamma Radiation is specifically referring to EM radiation produced from the nucleus of an atom. There are more ways than just matter-antimatter annihilation to produce it. And no, chemical reactions do not produce it.

    Nuclear Fusion does produce gamma rays typically. But this is NOT happening here.
  26. Jul 17, 2011 #25
    I am reading the wiki... that's how I'm learning, that and forum threads help sort things through... and I do appreciate you helping.

    So... This was mentioned in the thread already which I think is interesting.

    "University of Florida lightning expert Dr. Martin Uman says, "Observers of
    thunderstorms, from antiquity to the present, have noted that a heavy gush of rain
    often reaches ground a minute or two after a lightning flash and its accompanying
    thunder." He explains that questions about the relationship between lightning, thunder
    and rain gushes were finally resolved in the 1960s, when radar observations of
    precipitation in clouds before and after lightning confirmed that, in some cases, a gush
    followed the flash.

    Researchers postulate that cloud droplets near a lightning channel and its many
    branches acquire such intense charge that they repel each other, flying outward and
    colliding with non-charged drops, thereby growing large and falling as a rain gush."

    http://blog.chicagoweathercenter.com/2008/06/do-bursts-of-heavy-rain-follow.html [Broken]

    (There are papers on it too, but that is clearer)

    So this seems probable in the sense that perhaps lightning causes rain droplets to charge and bounce into each other. However, wouldn't this basically mean that during every lightning flash, we should expect a gush of rain to follow? I mean during the downpour, once a flash occurs that would charge the rain causing it to drop faster? And during periods of non-lightning, and non-thunder the rain would be a lighter downpour.

    It should be predictable to one degree or another, in rhythm for a lack of a better term, correct?
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