This is a solar eclipse. One like you have probably never seen before, taken by NASA’s Solar Dynamic Observatory in space. It looks really weird, as if the sun is fizzling away, fading into the darkness of space. Why is the edge of the shadow fuzzy?
Every six months, SDO goes into what NASA calls an “eclipse season”. For more than an hour a day, the spacecraft goes behind the Earth. So what you are seeing here is not a typical solar eclipse, where the sun hides behind moon. Here it’s hiding behind Earth, with more than half still out of our planet’s silhouette. That’s why the edge is fuzzy and convoluted in such a strange way: Earth’s contour is distorted by our atmosphere, something that the moon doesn’t have.
Our planet’s atmosphere – composed roughly by 79 per cent nitrogen, 20 per cent oxygen, and 1 per cent other gases – doesn’t have an even, clean edge. Its density changes, blocking the sun’s light with different intensity. But what about those weird swirls of fire getting into the shadow, making our home star look like it’s dripping magma? They are brighter spots on its surface. Or solar demons coming to Earth. One of those. [NASA Goddard Flickr]