I was going through my copy of Secret Lives of the US Presidents by Cormac O’Brien (which I bought simply because the name was too intriguing to pass up) and saw that Jimmy Carter was reputed to have seen a UFO. I think the fact that we have had a president report a UFO shows how ingrained the belief, or at least the want to believe, in extraterrestrials is. Whatever your opinion on the existence of life elsewhere in the universe, this is still an interesting topic. I think it also says something about Jimmy Carter - that he not only saw what he believed to be a UFO - but that he reported it.
Carter reported seeing a UFO in October of 1969. The Presidential UFO Website has a copy of Carter’s UFO report and letter about it scanned in. The Humanist magazine printed an article in it that stated what President Carter saw was actually the planet Venus. The article goes on to state that many UFO sightings are actually Venus:
Mr. Carter is in good company in misidentifying Venus as a UFO. Many highly trained and responsible persons, including airplane pilots, scientists, policemen, and military personnel, have made the same mistake. During World War II, U.S. aircraft tried to shoot down Venus on numerous occasions, believing it to be an enemy aircraft. In October of 1973, Ohio Governor John Gilligan made headlines by reportedly sighting a UFO. Governor Gilligan's "UFO" turned out to be a misidentification of the planet Mars.
This site also had a typed (versus scanned) copy of the Carter UFO report. It also copies an article (from The National Enquirer so I can’t say I much care for this article’s veracity) that said the Carters once lived in a haunted house in Georgia.
While I would advocate being skeptical of some of the sites, this is still a fun topic to delve into for a time.