This is a comet. The head of the comet is dust and gas that surrounds
the comet's nucleus. This will typically look round or, if the tail is
bright,parabolic in shape.
Tail: When the comet comes close to the sun, the dust and gas is pushed
away from the comet's head. this extension from the coma is called the
tail. Tails typically point away from the sun. They can be straight, curved,
or fan-shaped. A comet can have more than one tail. Tails can be quite
bright or rather faint.
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Comet Hale-Bopp
Discovered July, 23 1995
Was 100 million miles away from Earth.
False color image of comet.