On the evening of August 4, 1990, two men were walking on the moors above Calvine, a small hamlet in Perthshire, Scotland, when they witnessed an unknown diamond-shaped craft while seeking shelter under nearby trees.
The object hovered silently above them for approximately ten minutes, during which time one of the men captured six photographs of the craft. The witnesses described a large, diamond-shaped object that made a low humming sound. After hovering, the craft ascended vertically and disappeared at great speed.
During the sighting, a jet aircraft—identified by the Ministry of Defence as a Harrier—made several low-level passes as if the pilot had seen the object and was homing in for a closer look.
The two witnesses reported their sighting to the Daily Record, a Glasgow-based tabloid newspaper, and handed over their prints and original negatives. The materials were subsequently passed to the Ministry of Defence, but the originals subsequently disappeared. The identity of the witnesses remains unknown despite extensive efforts to locate them.
Former MOD desk officer Nick Pope, who served on what was known as "the UFO desk" from 1991 to 1994, described the Calvine sighting as "one of the most intriguing in the Ministry of Defence's files."
According to Pope, expert analysis undertaken by the MOD concluded that the photographs were "not fakes" and the sighting was marked as "object unexplained, case closed, no further action." MOD analysts determined the object to be a "solid craft," at least the size of a Harrier or Hawk fighter jet.
Documents released by The National Archives in 2009 included a government briefing from the MOD Secretariat Air Staff and a handwritten summary from a Sec(AS)2 officer, both dated September 1990. Additionally, poor-quality photocopies of Vu-Foils (images on transparent plastic) made from cropped versions of the original photographs were included in records from DI55, a branch of the Directorate of Scientific and Technical Intelligence.
In 2018, investigative journalist David Clarke renewed his investigation into the sighting, seeking to locate both the missing photographs and the witnesses. His interest was sparked by a Defence Intelligence Officer's claim that the witnesses had photographed a classified U.S. black project platform that remains Top Secret to this day.
In October 2021, Clarke contacted retired RAF Press Officer Craig Lindsay, who had received a print of one of the images from the Daily Record in 1990. In June 2022, Lindsay agreed to donate the original photograph—along with its envelope and the photocopies he had faxed to the MOD—to Sheffield Hallam University's Special Collection.
Andrew Robinson, a Senior Lecturer in Photography at Sheffield Hallam University, conducted an in-depth analysis of the original image. His analysis concludes that the photograph is genuine and that "as far as can be determined the image itself is a genuine photograph of a scene before the camera."
On the reverse of the original Calvine photograph, written in chinagraph pencil, is a handwritten credit which reads "Copyright Kevin Russell c/o the Daily Record, Glasgow." Clarke contacted the Daily Record, who confirmed that no-one by that name had ever worked there as a staff or freelance photographer.
Clarke and his research team carried out an intensive search, contacting more than 400 people by that name worldwide. A photograph of someone known by that name, who worked as a kitchen porter at a hotel in Pitlochry in the summer of 1990, was provided by a former co-worker and first published in the Daily Record in March 2023.
However, when the person identified was finally tracked down in 2024, he denied any knowledge of the UFO. Despite widespread coverage of the search in the media, no one has come forward and the witnesses' identities remain unknown.
The Calvine photograph has been described by multiple news outlets as "the best UFO picture ever," "the best-ever photo evidence," and "the world's clearest UFO photo."
Sean Kirkpatrick, former director of the United States Department of Defense's All-domain Anomaly Resolution Office (AARO), has been quoted as concluding that the image may be a reflection in a lake and that the photo has been doctored.
David Clarke was told by a Ministry of Defence officer that people at the Ministry knew the object was "an experimental craft belonging to the US." This has led to speculation that the photograph may show a classified military aircraft, possibly connected to the alleged Aurora program.
The MOD's original investigation concluded that the photographs were not fakes and marked the case as "object unexplained, case closed, no further action." The object's size was estimated to be at least as large as a Harrier or Hawk fighter jet.
The original negatives and prints disappeared from the Daily Record and were subsequently lost to public view until Craig Lindsay's donation in 2022. The witnesses' identities remain unknown despite extensive research efforts.
Photographic analysis by Sheffield Hallam University found no evidence the image was staged, though this possibility could not be definitively ruled out. The case remains unresolved, with competing explanations ranging from secret military aircraft to extraterrestrial craft.