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Small Comets, Dr Louis Rich, & Water In Space

  1. Jan 20, 2006 #1
    Lately, I have become quite interested in how the astronomy field has begun to determine that water can be found almost anywhere. And since it is the second most common molecule in the galaxy, at least here, I became intrigued with how it gets around so easily.

    This brings me to Dr Louis Frank, from the University of Iowa. Since the late 80s, he and some others have stated that they believe the presence of small comets are continually entering the earth's high atmosphere and seeding our planet with enough water to raise the level of water one inch every 20,000 years.

    There is quite a bit of information on the internet about this, but strangely, around 2000, the information comes to a halt. Not only that, but is seems that it is not entirely an accepted theory among the science community.

    This speech by Dr Frank, in 1999, seems to suggest that the debate is closed, yet I simply cannot find anything else since 2000.

    Does anyone have any more links, or information on this intriguing concept. I am inclined to agree with this theory, but I am a bit skeptical in concurring with the total number of small comets hitting the earth's atmosphere on a daily basis, as Dr Frank believes.

    The reason why this is important is that should there be so many small comets whirling around the solar system, traveling from one point to another, it could be quite dangerous. The odds of hitting one of these would be high. However, with that much water floating around, we would have no trouble finding enough to sustain us.

    Anyone know about this?
  2. jcsd
  3. Jan 26, 2006 #2
    I dont know if this will help you, but I've found an article written on March 1, 2001 with a fairly good picture and a few very discriptive paragraphs about the comets and a little about Dr. Frank himself.


  4. Jan 26, 2006 #3
    Water of the Heavens

    check this link

    this meteorite falls over texas, and people from nasa found water on it

    http://www.space.com/scienceastronomy/astronomy/meteorite_water.html [Broken]

    Last edited by a moderator: May 2, 2017
  5. Jan 27, 2006 #4
    interesting...it's water but not normal...wish i had witnessed the fall of the meteorite:smile:
    Last edited by a moderator: May 2, 2017
  6. Jan 27, 2006 #5
    What I once found interesting years ago was a TV program, I believe it was TLC, that showed scientists heating up the interior of a metiorite, and showed how water was present . I was amazed. Aparantly all rocks from space have water locked within them.

    The longer we explore and investigate the solar system, the more water we keep digging up all over the place. 20 years ago, if this was proposed, scientists would simply laugh out loud.
  7. Jan 27, 2006 #6


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    The most abundant element in the universe is hydrogen about 75% by mass,
    the next is helium about 23% by mass, but that doesn't do anything,
    the 2% remaining constitutes everything else of which the next most abundant element is Oxygen!

    It is therefore not surprising that water is very common in space, it is in fact the most common compound in the universe.

    Liquid water is very rare but ice is to be found everywhere the temperature is cold enough.

    Remember that next time you are swimming!:smile:

  8. Jan 27, 2006 #7


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    Welcome to Physics Forums, JohnL! :smile:

    I can't help you about the dates, but this 'dark comet' thing was quite a controversy. From memory, here's the story:
    - a researcher (Dr Frank?) examined farUV images of the Earth's upper atmosphere returned by a spaceprobe designed to study the upper atmosphere
    - he found what he claimed were the footprints of loose, fluffy water comets disintigrating in the upper atmosphere ('holes' in the EUV emitted, IIRC), and wrote a paper (or merely a letter?) for Nature (or some other publication?)
    - the paper was accepted for publication, and a storm of controversy ensued (the editor later said it was the biggest mistake of his professional career to have permitted the paper to published)
    - several people set out to independently verify the data (examining the same raw data that Dr Frank used), and the result (looking for such 'comets' in ground-based all-sky monitor images, for example)
    - with one or two marginal exceptions, no one could verify or validate the results
    - what really killed the idea, however, was that if there were such a rain of these objects onto the Earth, there should be a comparable rain onto the Moon, and the footprints of such would be very obvious (no atmosphere to cause the bodies to disintigrate, so they'd create craters, just like any other impactor; the rate claimed by Dr Frank would mean thousands and thousands of these small craters)
    - no such evidence can be seen - either by looking for such a population of fresh young small craters or contemporary impacts (e.g. looking at the unlit side of the Moon, for flashes when these comets would impact).

    So, while an interesting idea, it's been pretty thoroughly shown to be non-existant. So what did Dr Frank see in those images? Most likely just instrumental defects, noise, etc ... i.e. the bane of any observer's life!
  9. Jan 28, 2006 #8
    Your point is valid, but only to a certain level. Perhaps you did not know that UI sent up another camera into orbit in the second half of the 90s, and the very same things occurred with the new lens that was developed just for this sort of thing. So lense imperfections, and noise are pretty much ruled out.

    It may be that some middle ground is going to be the final result. It is entirely possible that Dr Franks estimation of small comet size is overestimated, and they are much smaller than he envisions. But it is clear that water is all over the solar system, and it has to have come from somewhere.

    Most likely, the seeding of the earth is less than he estimates, as the majority of these snowballs are consumed via the sun, and the planets. While this may have been the overwhelming case during a younger solar system, it may still exist, yet with less frequency.

    I certainly hope so, as space travel would be much more dangerious the other way.
  10. Jan 28, 2006 #9


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    I forgot another 'killer' observation (or rather, the absence of an observation, despite much looking): water on the Moon.

    If these objects were as Frank (I think his name lacks an 's') claimed, then they will have been colliding with the Moon too. If so, where's all the water (on the Moon)?

    Not just vast sheets of ice, but the water vapour released every time one of these impacts the Moon (and if they hit 'at night', then at least some of the water would be deposited as ice, to be turned into vapour as the Sun rose - so there should be at least a morning terminator very thin water vapour atmosphere). AFAIK, the lower limits on the amount of (transitory) lunar water vapour atmosphere is far below that which should be there, given Frank.
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