How Big is the Earth?

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The distance around the Earth, that is, it's circumference around the equator is 40,091 kilometres. The diameter (the distance across the centre of the Earth) at the equator is 12,756 kilometres. The Earth is slightly smaller when measured between the poles (12,713 kilometres), so it is not an exact sphere. If the Earth is weighted on a weighing machine, it would be nearly 6x10 tonnes.

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