The Moon can block the Sun completely during a solar eclipse because the Sun is far, far away. Is it then pure coincidence that the Moon almost completely fits the Sun’s outline, or could we’ve had solar eclipses with a much smaller Moon, thus blocking the sun only very partially?

Question

Title.

In: Physics

Answer 1

It’s coincidence, and we’re right on the border of the moon being too far.
The orbit of the moon is just oval enough that sometimes it is too far and we get something call an [annular eclipse](https://en.wikipedia.org/wiki/Solar_eclipse#/media/File:Annular_Eclipse._Taken_from_Middlegate,_Nevada_on_May_20,_2012.jpg) where the moon doesn’t block the sun all the way.
Though other times it’s close enough to block the sun all the way.