Solar prominence - or UFO?

Posted by Emma Woollacott

Is this a picture of a Death Star-type UFO refueling on the surface of the sun? Well, no.

But the tin-hat brigade are all very excited by a video posted this week on YouTube - check it out below - which appears to show a dark, spherical object tethered to the solar surface.

The name of the person who posted the video, Sunsflare, indicates that he's got some idea of what's really going on.

"This particular object is really very common on the sun. This is part of what's called a coronal cavity," explains C Alex Young, a solar astrophysicist at NASA's Goddard Space Flight Centre.

"So filaments, when you see them on the solar disk, in certain wavelengths appear dark because they're cooler material in relation to what's in the background."

When they're seen against the background of space, rather than the sun, they look brighter. They're known as prominences, and are quite common before CME eruptions - and, indeed, one soon followed.

"This is a pretty cool event and there's a lot of interesting structure, but this is very, very common for the corona," says Young.

Still, we like some of the other explanations much better - especially the one about it being some sort of cosmic sperm fertilizing the sun. The alien fleet trying to cool our star down sounds pretty good too.

Other suggestions include a black hole - "NASA probably knows about it but they won't tell the media". You're right, Krysskross123, they haven't.