Identified flying objects (IFOs)

The actual percentages of IFOs vs. UFOs depends on who is doing the study and can vary widely depending on the used database, evaluation criteria, personal biases, and politics. Results can also fluctuate from year to year. For details, see Identified flying objects

Hoaxes

Among the many people who have reported UFO sightings, some have been exposed as hoaxers. Not all alleged hoax exposures are certain, however, and many claimants have stuck by their stories, leaving the determination of specific cases as hoaxes contentious. Some of the controversial subjects include these:

* Perhaps most notably, Ed Walters' 1987 hoax, perpetrated in Gulf Breeze, Florida. Walters claimed at first having seen a small UFO flying near his home, and then in a second incident seeing the same UFO and a small alien being standing by his back door after being alerted by his dog. Several photographs were taken of the craft, but none of the being. Three years later in 1990, after the Walters family had moved, the new residents discovered a model of a UFO poorly hidden in the attic that bore an undeniable resemblance to the craft in Walters' photographs. Various witnesses and detractors came forward after the local Pensacola newspaper printed a story about the discovered model, and some investigators now consider the sightings to be a hoax. In addition, a six-figure television miniseries and book deal were nearly struck with Walters.[59]
* Contactees such as George Adamski, who claimed he went on flights in UFOs. (Some believers even contend he had real experiences and later fictionalized others, leaving the subject murky.)
* Bob White (UFO hunter) has a UFO artifact
* Billy Meier, some of whose photographs have been discredited.
* The Maury Island Incident
* The Ummo affair, a decades-long series of detailed letters and documents allegedly from extraterrestrials. The total length of the documents is at least 1000 pages, and some estimate that further undiscovered documents may total nearly 4000 pages. A Jose Luis Jordan Pena came forward in the early nineties claiming responsibility for the phenomenon, and most consider there to be little reason to challenge his claims.[60]
* The Sci-fi channel ran an advertising promo of a UFO near the World Trade Center being seen by a group of tourists in a helicopter. Created prior to the September 11, 2001 attacks, the commercial used realistic special effects to simulate the encounter. The video has subsequently been aired on East Asian television and posted to video-sharing sites like YouTube as genuine footage.[61]
* A video was posted as genuine footage to Youtube.com by a "barzolff814". It depicts two large UFOs flying over an observer on a tropical island, said to be Haiti in the title "Haiti Ufo". The video was quickly debunked by rense.com, AboveTopSecret.com and other sites. The video was done entirely with CGI 3D Animation programs by French animator David Nicolas, also known as "Numero 6."[citation needed] It managed to fool many people; many still thoroughly believe that the video is real. The hoax was discerned by the identical palm trees in the video, which were the same as in a promo video for a 3D program called Vue Infinite.