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The earths like shield

  1. Jul 6, 2005 #1
    ive heard about the earth having a shield above it that fends off astriods and metorights can some please explain this to me and how long it will last and everything thank you its called the
    magnetic field

    Last edited: Jul 6, 2005
  2. jcsd
  3. Jul 6, 2005 #2
    Must I say more? Ha. Inside joke.
  4. Jul 7, 2005 #3


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    Hi cbsgorams, and Mr. dude! The earth's magnetic field offers some protection from cosmic rays and solar flares, but meteorites and asteroids are not affected. They come crashing through without a whimper. Fortunately, not many are asteroids.
  5. Jul 7, 2005 #4


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    Our atmosphere is a pretty good shield for most of the stuff that comes our way. Ever see a meteor?
  6. Jul 7, 2005 #5


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    Where "most the stuff" means the daily impact of dust and sand-grain sized debris. The larger the object, the more likely that it will make it through the atmosphere and hit the ground.
  7. Jul 7, 2005 #6


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    As the old guys said, the atmosphere is the only defense we have against physical masses larger than atoms. A bright meteor that you might see on a regular basis is about the size of a sand grain. Anything large enough to survive the fall and become a meteorite is visible as a pretty intense fireball. (I actually phoned the Detroit airport once when I was about 15 because I witnessed a boloid—exploding meteor—and thought that it was a plane going down.)
    The seething mass of radiation and subatomic particles that the magnetic field deflects would scare the **** out of you if you could see it. We live in one really nasty storm and happen to have a nice umbrella.
  8. Jul 7, 2005 #7


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    1- The magnetic field shields us from Nasty Solar flares. A good example of the magnetic field shielding us is the Aurora Borealis you see in the Northern Hemisphere.

    2- The Earth's atmosphere is made up of several layers consisting of Stratosphere, troposphere, mesosphere, ionosphere etc etc. They all have varying temperatures and pressures. Some of them are more than 2000F. Most foreign objects entering the Earth's atmosphere are burnt and melted through these layers. One example is the NASA spacecraft that crashed 2 years ago.
    However bigger objects do penetrate the Earth's atmosphere and land even though they would have suffered some level of burns.
  9. Jul 8, 2005 #8
    Ha ha ha!!! The last part of this post is a very good way to describe it. :rofl:
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