Asked by: Ashley Martin, Chawton
It depends on the type of eclipse. During a total eclipse of the Sun, the Moon covers the whole solar disc, and to do this the Sun has to be around 400 times further from the Moon than the Moon is from the Earth. If the ratio is smaller, the Moon no longer completely covers the solar disc, and so produces an annular eclipse, which features a ring of light around the Sun.
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Authors
Robert is a science writer and visiting professor of science at Aston University. He likes maths, West End musicals and hamsters.
