The Universe - Mercury

Mercury is the planet closest to the Sun.  

 Even so, it is 58 million kilometres away from the Sun.



Mercury orbits round the Sun, but its orbit of the Sun lasts for only 88 days.

Mercury is a small planet.  

Its diameter is only 4990 kilometres.  

In many ways it resembles the Moon, with dark and light areas, and many craters caused by impacts.

 A transit is the passage of a planet across the Sun's bright disk. At this time, the planet can be seen as a small black disk slowly moving in front of the Sun. 

 Mercury Transit Path on 9 May 2016

 The orbits of Mercury and Venus lie inside Earth's orbit, so they are the only planets which can pass between Earth and Sun to produce a transit. 

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