The UFOMania channel posted this video made from images taken by NASA's STEREO satellites that show a large sphere passing ahead.
Other frames in the series do not feature the Sun-like sphere, nor does any image from October's captures from the mission.
The two STEREO craft were launched 10 years ago to take images of the Sun from opposing sides, to allow solar phenomena like coronal mass ejections to be better observed.
To read more and view the video, click here.