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Moon's crust as fractured as can be

  1. Sep 16, 2015 #1
    Moon's crust as fractured as can be

    Scientists believe that about 4 billion years ago, during a period called the Late Heavy Bombardment, the moon took a severe beating, as an army of asteroids pelted its surface, carving out craters and opening deep fissures in its crust. Such sustained impacts increased the moon's porosity, opening up a network of large seams beneath the lunar surface.

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  2. jcsd
  3. Sep 17, 2015 #2
    How did the moon take so many hits but the Earth relativity unscathed?
  4. Sep 18, 2015 #3


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    I don't think it did.

    From wiki: https://en.wikipedia.org/wiki/Late_Heavy_Bombardment

    The Late Heavy Bombardment (abbreviated LHB and also known as the lunar cataclysm) is a hypothetical event thought to have occurred approximately 4.1 to 3.8 billion years (Ga) ago,[1] corresponding to the Neohadean and Eoarchean eras on Earth. During this interval, a disproportionately large number of asteroids apparently collided with the early terrestrial planets in the inner Solar System, including Mercury, Venus, Earth, and Mars.
  5. Sep 18, 2015 #4
    But Earth's crust is in good order, right?
  6. Sep 18, 2015 #5


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    We have tectonic activity, and also a higher surface gravity and liquid water to "fix" rough structures.
  7. Sep 18, 2015 #6
    You mean the Earth has a kind of puddy or spackling? :smile:
  8. Sep 18, 2015 #7


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    What is "puddy"?

    Parts of the crust get submerged below other parts, enter the molten mantle and melt, while elsewhere new crust material solidifies out of the mantle.
    The oldest known parts of the crust are about 4.3 billion years old (older than the late heavy bombardment), but most parts are younger.

    Add erosion, the tendency of water to enter underground cavities (which can speed up a collapse), earthquakes, ... and cavities have a hard time surviving for long timespans.
  9. Sep 18, 2015 #8
    Like what you use to patch a hole in dry wall :biggrin:
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