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The big splat theory

  1. Feb 4, 2005 #1
    I've been reading 'The Big Splat, or How Our Moon came to Be' by Dana Mackenzie. This describes how at a meeting in 1984, the consensus was quickly reached that the moon formed when a Mars-size planetoid collided with the Earth soon after its origin.

    What I found a bit surprising is that if this new idea suddenly became accepted, then why doesn't it seem to have entered the public consciousness very quickly? I have to admit that before reading the book I hadn't really taken in this idea, although I'd probably read about it in passing a few times. Contrast this with ideas such as a meteor impact causing the extinction of the dinosaurs, or of the acceleration of the expansion of the universe. These ideas seemed to spread quickly, being discussed in many popular science books and TV problems.

    So have I just missed the spread of this idea until now? Have other people come across this idea, heard it discussed etc., and if so, when did it seem to enter the popular mindset? If not then why not? Is the origin of the moon less interesting than the ideas above? I would have thought it would be something everyone could relate to, especially the generation brought up with the moon landings (the data from which lead to this idea).
  2. jcsd
  3. Feb 4, 2005 #2


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    If you happen to be in the vicinity of the Goddard Space Flight Center in Greenbelt, Md on April 5, you can hear Dana Mckenzie, founder of the big splat theory, tell the story. http://ecolloq.gsfc.nasa.gov/announce.mackenzie.html [Broken]
    The theory gained credence after study of moon rocks retrieved during the Apollo program.
    Last edited by a moderator: May 1, 2017
  4. Feb 5, 2005 #3


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    The lack of dead dinosaurs doesn't help. Also, it hasn't been taken up by any of the great popularizers of science. Asimov, Sagan, Hawkings, Dawkins and Feynman all pretty much overlooked it, for example. Sagan would have been the only real logical one of that list to make the case, but he focused on other points.
  5. Feb 6, 2005 #4


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    According to this web page:


    the collision theory was presented in 1974 by William Hartmann and Donald Davis. Harvard researcher A. G. W. Cameron and William Ward were working on a similar model, and published their findings in 1976. The 1984 conference in Hawaii established the viability of the theory, but it had already been around for 10 years.
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