July 8, 2013 at 5:32 PM ET
Sixty-six years after newspaper headlines heralded the discovery of a "flying saucer" in Roswell, N.M., the famous 1947 UFO incident is passing from the realm of eyewitness accounts into the realm of legend.
That legend came to life again for the anniversary, in the form of a Google Doodle game that lightheartedly retraces the Roswell story. The International UFO Museum in Roswell celebrated the incident last weekend at its annual festival.
The real-life event centers around reports of a crashed UFO and supposed sightings of alien bodies in the vicinity of Roswell in July 1947. At first, the U.S. Air Force said that a flying disk had been found — but that report was quickly retracted, and the military said instead that the "saucer" was nothing more than a weather balloon that fell to Earth.
Some of those who figured in the story are still alive — for example, Glenn Dennis, the mortician who fielded calls from Roswell Army Air Field about how to handle small bodies. Many others have passed away, however — and the authorities say they've closed their X-Files for good.
The U.S. Air Force stamped "Case Closed" on its file back in 1997, when Roswell fans were marking the 50th anniversary of the incident. The final report said that the mysterious debris was actually wreckage from balloon-borne experiments to monitor Soviet nuclear blasts, and that the bodies were probably crash dummies used to judge the effect of high-altitude falls.
Just this March, the FBI issued a statement following up on a 1950 memo in its files, reporting that "three so-called flying saucers" had been recovered in New Mexico. The bureau said it never followed up on what it called an "unconfirmed report," apparently because it wasn't judged worthy of further investigation. Other UFO investigators have said the flying-saucer claims seem to have been part of an intentional hoax that was spawned by the Roswell incident and made its way into the FBI's files.
The official denials haven't put a dent in the UFO legend. In honor of the anniversary, here are some of the more recent twists in the Roswell tale:
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" theNBC News Science Facebook page, following @b0yle on Twitter and adding +Alan Boyle to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.