Black Knight satellite conspiracy theory

1998 NASA photo of space debris, an object believed by some conspiracy theorists to be an extraterrestrial satellite, the Black Knight

The Black Knight satellite conspiracy theory claims that a spacecraft of extraterrestrial origin is in near-polar orbit of the Earth, and that NASA is covering up its existence and origin. This conspiracy theory combines several unrelated stories into one narrative.

A photo taken during the STS-88 mission claimed by some to show the Black Knight satellite is catalogued by NASA as a photo of space debris, and space journalist James Oberg considers it as probable debris of a thermal blanket confirmed as lost during the mission.