The first and fastest planet! Mercury is the planet closest to the Sun. It is a rocky body with a thin atmosphere and no moons. Due to the practically non-existent atmosphere, Mercury is also heavily cratered. Mercury's orbit is the most eccentric out of all the planets, meaning its orbit is the most least like a circle. A year on Mercury is 88 Earth days, but a single day on Mercury is 116 Earth days! The Sun's gravity latches on to small little Mercury and makes the days super long. Sometimes Mercury goes into retrograde, an optical illusion that makes the planet appear that it's moving backwards in its orbit. This is just cased by the fact that both Earth and Mercury are both moving, and at different speeds.

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