Planets & Solar System “Mercury has a diameter of 4,880km (3,032 mi); the Sun’s is 1,392,000km (865,000 mi)” Mercury size comparison The Earth is about 2.54 times the size of Mercury
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very planet is unique, but Mercury is a planet of paradoxes and extremes, and that’s just based on what we know so far. It’s the innermost planet, the smallest planet and has the most eccentric orbit. We’ve known about its existence since the third millennium BC, when the Sumerians wrote about it. But they thought that it was two separate planets – a morning star and an evening star – because that’s just about the only time you can see it due to its closeness to the Sun. The Greeks knew it was just one planet, and even that it orbited the Sun (long before acknowledging that the Earth did, too). Galileo could see Mercury with his telescope, but couldn’t observe much. This little planet has a diameter that’s 38 per cent that of Earth’s diameter – a little less than
