The dark object was spotted during footage taken by the Moon Live Stream, and it has excited UFO investigators as it is not the first time such a sighting has happened.
Sceptics dismiss these objects as satellites placed into orbit by space agencies on Earth.
Other suggestions are they could even be weather balloons that appear to be much closer to the moon on the live stream than they actually are.
But paranormal investigators say they can rule these explanations out.
Scott C Waring, editor of ufosightingsdaily.com, said: “As luck would have it, this UFO was caught on live stream when they were checking out the moon.
“It was caught by SpaceImaging Keith of Youtube.
“The UFO is not a satellite, which would travel in a straight line. This UFO zig zags as it moves forward. It is not a balloon, because a balloon does not zig zag as it travels.”
He is convinced it can only be an intelligently flown alien space craft, or some other top-secret Earth-based project.
This is because he claims there have been a number of other previous similar sightings, including one he claims could have been an enormous mothership.
He added: “Dark disks have been seen traveling over the moon many times before. This is not the first, nor will it be the last.
“The most memorable dark disk was a UFO that measured over five miles across and was caught by an amateur Italian astronomer while cleaning his optics on his telescope and had it on record at the time.”
The latest object was seen on the live stream on August 10 this year.