Page 20 - COSMOS & H -Health - Science
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Comet 103P/Hartley (Hartley 2) is a small, oval (or
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Comet 103P/Hartley (Hartley 2) is a small, oval (or
C C o m e t t 1 1 0 3 P / H a r t t l l e y ( ( H a r t t l l e y 2 ) ) i i s a s m a l l l l , , o v a l l ( ( o r
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peanut) shaped comet -- its nucleus measures
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peanut) shaped comet -- its nucleus measures
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approximately one mile (1.6 kilometers) in diameter. . .
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approximately one mile (1.6 kilometers) in diameter.
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I I It takes Hartley 2 about 6.47 years to orbit the Sun
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It takes Hartley 2 about 6.47 years to orbit the Sun
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once. Hartley 2 last reached perihelion (closest
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once. Hartley 2 last reached perihelion (closest
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approach to the Sun) in 2017. .
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approach to the Sun) in 2017.
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The force exerted on the comet by the Sun’s radiation, pressure and
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The force exerted on the comet by the Sun’s radiation, pressure and
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solar wind causes streams of dust and gas to be released. These
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solar wind causes streams of dust and gas to be released. These
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it approaches nearer, an enormous “tail” is formed. This tail points
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it approaches nearer, an enormous “tail” is formed. This tail points
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nucleus of the comet, is about 50 kilometers in innucleus of the comet, is about 50 kilometers in
nucleus of the comet, is about 50 kilometers
nucleus of the comet, is about 50 kilometers in
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diameter. However, the tail or the coma following the
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nucleus could be greater than the size of the Sun itself!
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nucleus could be greater than the size of the Sun itself! !
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In some cases, it has been measured to be 3.8AU long. .
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In some cases, it has been measured to be 3.8AU long.
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(AU is Astronomical unit which is the distance from the
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