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Moon enters Earth's atmosphere

  1. Dec 4, 2004 #1
    If the moon ever did enter our atmosphere, what would be the first thing that would happen? How would the two gravitational fields interact with each other?
  2. jcsd
  3. Dec 4, 2004 #2


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    The Moon could never enter the atmosphere in one piece. Long before it got that close it would be torn apart by tidal forces. The closest it could get before it broke up would put the surface of the moon about 6400 miles from the surface of the Earth. The atmosphere is generally considered to reach to about 62 miles above the surface of the Earth.

    As far as interaction between the gravitational fields, that already happens. It is just such an interaction that holds the Moon in its present orbit. Gravitational interaction is also what would break the moon up when it got too close to the Earth.
  4. Dec 4, 2004 #3


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    Or if you really want to get hypothetical, a rogue instellar planet passes through our solar system, passes near the Earth/Moon, robs the Moon of its orbital velocity, and the Moon drops straight to Earth. Then it wouldn't have time to get ripped apart by being inside the Roche limit.

    If this were the case, the Moon could take as long as 1 week to drop to Earth. Even on day 1, tides would be noticably larger, but each day, they would grow exponentially. The final week would probably see many strong earthquakes, possibly violent volcanic eruptions and massive coastal flooding.

    When the Moon finally did hit the atmosphere, it would just burn up like a shooting star, end of story... :cool:

    Just kidding. The atmosphere can't stop the Moon. From the time it first hit the top of the atmosphere, it would take about 6 seconds to make it to the surface before the most violent collision since the early days of the solar system occured. Earth as we know it, and all life on Earth would instantly be no more. :bugeye:

    Cool question :surprised
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