From our perspective here on Earth, one of the most spectacular celestial dances appears when the Moon partially obscures our view of the Sun, allowing a ring of star fire to escape its edges. And on June 21, that’s exactly the show we’ll be getting.
The phenomenon is called an annular solar eclipse. It happens when the Moon is farthest away from Earth in its orbit, and therefore appears smaller in our skies relative to the Sun.
That small difference in apparent size is what sets annular eclipses apart from full solar eclipses, when the closer position of the Moon (with its average radius of 1,800 kilometres or 1,000 miles) makes it appear to be the same size as our far larger star, which has a radius of around 696,000 kilometres (432,000 miles).
A stunning – and unusual – example of this was captured by photographer Colin Legg and astronomy student Geoff Sims in Western Australia in May 2013.