Encyclopaedia Britannica’s authoritative entry on “unidentified flying object” (last updated April 22, 2026) is written by Seth Shostak, astronomer at the SETI Institute — marking the formal convergence of SETI and UAP as a single scientific domain in mainstream reference material. Key facts Britannica confirms as encyclopedically established: (1) J. ALLEN HYNEK — The astronomer hired by the U.S. Air Force as its official UFO skeptic and Blue Book scientific adviser for all three projects (Sign, Grudge, Blue Book) concluded after decades of investigation that “a small fraction of the most-reliable UFO reports gave definite indications of the presence of extraterrestrial visitors.” He founded CUFOS in 1973. The man paid to debunk them ended up a believer. (2) DUAL GOVERNMENT DISINFORMATION — Britannica confirms: “In the Soviet Union, sightings of UFOs were often prompted by tests of secret military rockets. In order to obscure the true nature of the tests, the government sometimes encouraged the public’s belief that these rockets might be extraterrestrial craft.” The US was simultaneously using “ice crystals” and “temperature inversions” to cover U-2 spy planes. Both Cold War superpowers used the extraterrestrial narrative as a military disinformation tool — in opposite directions. (3) AATIP MATERIALS — Britannica confirms the most newsworthy aspect of AATIP going public in December 2017 was “a report that the U.S. government possessed alloys and compounds, purportedly obtained from UFOs, that were unidentifiable.” (4) ROBERTSON PANEL SECRECY — “Parts of the panel’s report were kept classified until 1979, and this long period of secrecy helped fuel suspicions of a government cover-up.”