Between 1947 and 1969, 12,618 sightings were reported to Project Blue Book, a project into UFO research that was headquartered at Wright-Patterson Air Force Base. To this day, 701 of the sightings remain "Unidentified."
One of the first and most famous involved businessman and pilot Kenneth Arnold, who was flying near Mt. Rainer, Wash. on June 24, 1947, when he reportedly sighted nine unidentified flying objects. The press later used his various descriptions to come up with the term flying saucer.
On July 8, 1947, Roswell, New Mexico's public information office announced the recovery of a crashed "flying disc" from a ranch near Roswell. The military said what was recovered was debris from an experimental surveillance balloon which was part of a classified program.
Critics who charge the government with covering up the truth maintain that an extraterrestrial spacecraft and its occupants were found near Roswell a finding kept secret from the public.
Captain Thomas Mantell, a 25-year-old pilot in the Kentucky Air National Guard, crashed and died on January 7, 1948, while pursuing a supposed UFO. Mantell was an experienced airman who had seen considerable action as a World War 2 pilot. The circumstances leading up to his crash have been a matter of dispute. The two pilots flying with Mantell were unable to clearly identify the object that was under pursuit.
George Gorman's Depiction of a UFO Encounter over Fargo
On Oct. 1, 1948, George F. Gorman, a pilot in North Dakota's National Guard, flying at night over Fargo when he spotted what he later described as an object with a blinking light. The only other authorized aircraft in the region was supposed to be a Piper Cub. Approaching the UFO, Gorman said it resembled a ball of light that grew brighter and accelerated as he got near it. In a later sworn statement to investigators, Gorman said:
"I am convinced that there was definite thought behind its maneuvers. I am further convinced that the object was governed by the laws of inertia because its acceleration was rapid but not immediate and although it was able to turn fairly tight at considerable speed, it still followed a natural curve. When I attempted to turn with the object I blacked out temporarily due to excessive speed. I am in fairly good physical condition and I do not believe that there are many if any pilots who could withstand the turn and speed effected by the object, and remain conscious. The object was not only able to out turn and out speed my aircraft...but was able to attain a far steeper climb and was able to maintain a constant rate of climb far in excess of my aircraft."
Credit: Project Blue Book Archive
What did - or didn't -- happen at the Otis Air National Guard Base near Cape Cod, Mass. in the 1950s? The base had been rumored to be involved in several UFO reports - including one in which a F-94C Starfire supposedly disappeared. The Air Force has never confirmed those claims.
On November 23, 1953, First Lieutenant Felix Eugene Moncla, Jr. was ordered into the air to intercept an unidentified object that was tracked by radar operators in Sault Ste. Marie, Michigan. After closing in on the object, Moncla's plane disappeared from the screen and was never found.
Betty and Barney Hill claimed to have been abducted by aliens in 1961. While they were traveling on a road near Portsmouth, N.H., the couple said, a space ship landed and they were escorted inside the craft where they submitted to full-body inspections carried out by the aliens. The incident was subsequently portrayed in the movie "The UFO Incident."
In what became known as the Manises UFO incident, a Supercaravelle commercial flight flown by the airliner TAE was forced to make an emergency landing at Valencia, Spain on November 11 1979 after taking evasive action to avoid colliding with an unidentified craft. A jet fighter was subsequently scrambled from a nearby Spanish air force base. It was reported to have made brief visual contact, describing a short cone-shaped object with changing colors. The Spanish air force later said that both the commercial airliner as well as the jet fighter had mistaken "flashes emitted from a distant chemical industry complex" as well as by "some stars and planets
This one remains a mystery until today. On November 16, 1986, a Japan Air Lines cargo jumbo plane reported three unidentified objects while flying over Alaska. During an investigation carried out by the Federal Aviation Administration, the pilot, Kenji Terauchi, was reported to have said that he saw two small lights measuring no more than eight feet across. He said that a third, larger light was also visible on the craft.
Credit: Getty Images
Some would later refer to it as "Pennsylvania's Roswell." On Drcember 9, 1965, reports in several states talked of a fireball which left behind steaming metal debris. That wasn't all. In the town of Kecksburg, PA., eyewitness accounts talked of a large acorn-looking object landing. (See the replica in the accompanying image.) The base of the craft was said to be adorned with what could best be described as hieroglyphics. An army investigation would later fail to turn up evidence corroborating the reports. The object streaking across the sky was later said to be a meteor.