Quick & curious · Space

It's a coincidence the Moon covers the Sun almost exactly.

Total solar eclipse: the black disc of the Moon, surrounded by the Sun's bright corona
Photo: Luc Viatour · CC BY-SA 3.0 · Original

400×larger and farther away: the Sun

The story behind it

It's a coincidence the Moon covers the Sun almost exactly.

The Sun's diameter is about 400 times the Moon's, but it is also about 400 times farther away. That's why both look almost the same size. But the Moon moves about 3.8 centimetres farther away every year. In 650 million to 1.4 billion years it will no longer cover the Sun completely.

Sources

Every statement in this discovery is backed by one of these sources and was checked before publication.

  1. Wikipedia: Angular diameter (accessed 2026-10-07)
  2. Wikipedia: Solar eclipse (accessed 2026-10-07)