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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?
    Last edited by a moderator: Sep 25, 2014
  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.
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