A set of mysterious pictures of the Sun uploaded to NASA's servers have caused a furore in the UFO-hunting community, for showing what has been interpreted as a giant alien ship 'sucking life' from our star.
Needless to say, NASA isn't convinced (and neither are we).
So what is it? First, let's take the view of UFO Sightings Daily, who are convinced there is something unnatural at play. (Which is not unusual, by the way.)
Here's how they write about the above picture taken from this public archive:
"It shows a massive disk over the sun, and if you look carefully, you will see a small stream of energy twisting and going up to the UFO," the site writes. "hey are harvesting energy from the sun. Aliens may have high tech, but advanced civilizations with advanced tech has extremely high energy demands to meet. This is one way they get that need met."
Unfortunately for the UFO-hunters searching our skies for Mars apes and alien Supermen, there are probably one or two simpler explanations.
The first is that the picture might be showing a coronal mass ejection, a relatively regular occurrence similar to a flare in which the sun belches out huge amounts of energy in one go -- which would not be unexpected during the 'solar maximum' or heightened period of activity it's currently cycling through.
The other is that the UFO is a compression fault in the image. Nasa has presented evidence that this compression causes weird anomalies in its images before.
Dr. Joe Gurman at Nasa said on another controversy including images sent by the Stereo spacecraft that "What you're seeing is the difference between "beacon mode" (near real-time, heavily compressed, binned [I believe 512 x 512 or smaller]) images and normal playback telemetry images".
It's tricky to know exactly what's happening in the image - particularly as the links in the UFO Sightings story don't go straight to the image in question but a set of slightly different pictures. Don't lose any sleep over it, though.