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Solar System

Solar System (

Our solar system has eight planets. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Pluto's category as a planet is changed to a dwarf planet since 2006.

The planets closer to the sun completes their orbit faster than those further away. For example, Mercury takes 3 months to revolve once around the sun where as Neptune needs 165 earth years to complete.

Planets spin around their axis. Earth spins once every 24 hours. The some other planets will spin faster and some would be slower. Mercury spins onces every 1,408 hours and Jupiter takes 10 hours to spin.

Mercury, Venus, Earth, and Mars are terrestrial planets. They are called terrestrial planets because they are rocky and compact like Earth. Venus, Earth, and Mars have noticable atmosphere where as Mercury has no atmosphere.
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