The Solway Firth Spaceman
This is probably one of the most popular mysterious photos in the world. In 1964, near Solway Firth in Cumbria, England, Jim Templeton was taking a photo of his daughter in a meadow. She was the only one in view of the camera, but when they developed the film, they found a spaceman behind her. Modern analysis suggests it could be someone with their back turned, but Templeton claims that it was just he and his daughter out there.