Moon landings hoax conspiracy theorists claim to have found an identical backdrop in two different pictures from the Apollo 15 fourth lunar landing mission in 1971.
The pictures are said by NASA to have been taken some miles apart on the Moon during the mission.
They were apparently taken from different locations, as in one the lunar module is there and tracks are visible.
In the other, there is a more rocky surface seen in the foreground.
But, conspiracy theorists claim to have proved the scenes were both staged in a studio, with the same background.
They have laid the two pictures over each other and claim the backgrounds match and perfectly overlay each other.
Moon hoax believer David Percy, who has been an associate of the Royal Photographic Society, believes images were manipulated, and in the case of these two pictures a set backdrop was used for both.
He does not believe it would be possible for an identical horizon to have appeared from pictures taken in different locations.
He said: “Our research suggests that images of the Apollo landings are not a true and accurate record. In our view the Apollo pictures were faked. Many of the images are replete with inconsistencies and anomalies.”
NASA categorically denies all claims its Moon landings were hoaxed.
In terms of these pictures, it says because the Moon is smaller than Earth, horizons appear closer to the human eye than they really are, and may therefore look the same from different viewpoints.
The debunking website badastronomy.com has also investigated the claims in detail and concluded they are genuine pictures, and therefore the Moon landings were unlikely to have been hoaxed.
In an article about the two pictures, Ian Williams Goddard said: “Examination of the photographic archive of the Apollo 15 mission clearly proves that the mountains in the background are large and distant enough that they can be seen and look similar from myriad points of view with or without the lander in the foreground.
“The mountains we see above are the Apennine Front on the left side of each photo and Mount Hadley Delta to the right in each.
“Apollo 15 astronauts went up to those mountains and walked on Hadley Delta. How could they enter a fake backdrop?”
He said lunar surface panoramas made up of pictures taken within the mountains proved they were a three-dimensional real place and not a backdrop.
He added: “The panorama also gives a sense of how far the mountains are. Because there is no atmosphere on the Moon, objects do not become faded-out over distance and thus far-away mountains can appear very close, as they do in the two photos.”
“The claim that these known and mapped Moon mountains that are viewed from myriad angles in Apollo photos are really a fake backdrop that was accidentally used in two staged studio sets on Earth is not a theory but an exercise in silliness.”