The Mother Ship Has Not Landed

Um, what is that planet-sized object right next to Mercury (top right)? Image Source: Space.com.

On December 1, NASA's STEREO spacecraft photographed Mercury being enveloped by a Coronal Mass Ejection from the Sun. It also caught a curious, planet-sized object right next to Mercury. Conspiracy theorists and UFO enthusiasts, as well as Planet X Nibiru doom-seeking doomsdayers expecting Earth's 2012 collision with a Doppelgänger or Shadow Planet, are all abuzz.  They are convinced that the giant invisible body hiding next to Mercury is a huge alien Mothership, which is cloaked so that we can't (normally) see it. You can see a video with Mothership commentary, here. Space.com asked "scientists in the solar physics branch at the United States Naval Research Laboratory (NRL) — the group that analyzes data from the Heliospheric Imager-1 (HI-1), the telescopic camera that shot the new footage" what that thing is. They concluded that it is a data-processing artifact, the ghost of where Mercury was the day before, which appears as result of the way they process the information to produce the photograph.