The archival record
The National Archives preserves textual and audiovisual records associated with Project Blue Book. Its reference page reproduces a 1985 Air Force fact sheet describing the program’s termination in 1969.
Conclusions within their scope
The reproduced fact sheet reports 12,618 sightings for 1947–1969 and 701 categorized as unidentified. It states that the Air Force found no evidence that unidentified cases were extraterrestrial vehicles. These are attributed historical findings; an unidentified classification is not itself an explanation.
Connected knowledge
Explore connectionsSource trail
Report an evidence-backed correctionUse the Primary sources tab to inspect the original records, publication dates and provenance.