Meteors are ionized trails of particles (usually the size of dust grains) which enter the atmosphere and ionize the air due to compression and heating of the air along the track. Due to the very high velocity of such a particle, it creates a bow shock ahead of it, which compresses the air so much that it becomes ionized and starts glowing. Sometimes, a meteor is large enough to land on the ground, and the remaining object is then called a meteorite.
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