Exposed (UFO)
"Exposed" is the second episode aired of the first series of "UFO" - a 1970 British television science fiction series about an alien invasion of Earth. The screenplay was written Tony Barwick and the director was David Lane. The episode was filmed between 13 May to 23 May, 1969 and aired on the ATV Midlands network on 23 September, 1970. Though shown as the second episode, it was actually the fifth to have been filmed.
Ufology
The first official USAF investigations of UFOs were Project Sign (1947–1949) and its successor Project Grudge (1949). Several hundred sightings were examined, a majority of them having a mundane explanation. Some sightings were classified as credible but inexplicable, and in these cases the possibility of an advanced unknown aircraft could not be ruled out.
The initial memos of the project took the UFO question seriously. After surveying 16 early reports, Lt. Col. George D. Garrett estimated that the sightings were not imaginary or exaggerations of natural phenomena. Lt. General Nathan F. Twining expressed the same estimate in a letter to Brig. General Schulgen, and urged a concerted investigation by the Air Force and other government agencies. Twining's memo led to the formation of Project Sign at the end of 1947. In the summer of 1948, Sign's first intelligence estimate (Estimate of the Situation) concluded that some UFO reports were extraterrestrial in origin. The rejection of the estimate by USAF Chief of Staff Gen. Hoyt Vandenberg led to the dissolution of Sign and the formation of Project Grudge.