UAP disclosure timeline: a worldwide history

Governments around the world have investigated unidentified aerial phenomena. This timeline follows 16 countries and the UN from 1946 to today. It is a living list and is not yet complete — notably it has no entries from Africa or the Middle East. Reviewed October 2026; for newer developments see our latest coverage.

Entries record that something was investigated, announced or released — not what the object was. Inclusion is not a finding that any report involved extraterrestrial technology.

Year	Where	What happened
1946	Sweden	A wave of “ghost rocket” sightings over Scandinavia prompts a Swedish military investigation.
1947	United States	Pilot Kenneth Arnold reports nine fast objects near Mt. Rainier, popularizing “flying saucers.” The Roswell, New Mexico debris incident follows that summer.
1948–1952	United States	US Air Force investigations Project Sign and Project Grudge begin.
1950	Canada	Project Magnet: a Department of Transport engineer, Wilbert Smith, begins one of the earliest government-sponsored UFO studies.
1950–1951	United Kingdom	The Air Ministry’s Flying Saucer Working Party studies reports and concludes they have conventional explanations.
1952–1969	United States	Project Blue Book collects thousands of reports; most are explained, a portion remain “unidentified.”
1966	Australia	Students and teachers at Westall, near Melbourne, report a landed object — a sighting that remains a touchstone of Australian UFO history.
1967	Canada	Shag Harbour, Nova Scotia: witnesses report an object descending into the sea; the RCMP and military investigate.
1968–1969	United States	The University of Colorado “Condon Report” concludes further study is unlikely to be productive; Blue Book closes.
1977	France	GEPAN is founded inside the national space agency, CNES — the first standing, civilian government UFO study unit in a major space power.
1977–1978	Brazil	Operação Prato: the Brazilian Air Force investigates reports of lights and encounters in Pará state.
1977–1978	United Nations	Grenada’s prime minister, Eric Gairy, presses for a UN body to coordinate UFO research; the UN hears from researchers in 1978.
1978	Australia / New Zealand	Frederick Valentich disappears over Bass Strait after radioing about an unknown aircraft (October); weeks later a film crew records the “Kaikoura lights” off New Zealand (December).
1979	Uruguay	The Air Force creates CRIDOVNI, an official commission to receive and investigate UFO reports.
1980	United Kingdom	The Rendlesham Forest incident near US air bases in Suffolk becomes Britain’s best-known military-linked UFO case.
1986	Brazil	The “Night of the UFOs” (May 19): radar and visual contacts lead the Air Force to scramble jets; the government acknowledges the event.
1988	France	GEPAN is reorganised as SEPRA within CNES.
1989–1990	Belgium	A wave of reported triangular objects culminates on 30–31 March 1990, when radar contacts lead to two F-16s being scrambled; the Air Force publishes data on the case.
1992–2008	Spain	The Spanish Air Force begins declassifying its UFO files in October 1992, releasing them in batches over the following years.
1997	Chile	CEFAA, a government committee for the study of anomalous aerial phenomena, is established under the civil aviation authority.
1999	France	The COMETA report — a private study by former senior French military and space officials — argues the extraterrestrial hypothesis deserves serious consideration.
2000 / 2006	United Kingdom	The Ministry of Defence completes “Project Condign,” a secret UAP study; released in 2006, it finds no evidence of extraterrestrial craft and attributes many reports to natural phenomena.
2001	Peru	The Peruvian Air Force creates OIFAA, an office for investigating anomalous aerial phenomena.
2004	Mexico	A Mexican Air Force crew films multiple lights on infrared over Campeche; the footage is later widely studied.
2005	France	GEIPAN replaces SEPRA at CNES; its case files are later published online for anyone to read.
2008–2013	United Kingdom	The National Archives release the Ministry of Defence’s UFO files in tranches, ending in 2013.
2009	United Kingdom	The Ministry of Defence closes its UFO desk (1 December), saying reports had never shown a defence threat.
2010	New Zealand	The Defence Force releases hundreds of UFO documents (December).
2000s on	Brazil	The Air Force begins transferring its UFO dossiers to the National Archive; new batches continue to be released.
2014	Chile	Infrared footage from a Navy helicopter is investigated by CEFAA, which cannot identify the object.
2017	United States	The New York Times reveals the Pentagon’s Advanced Aerospace Threat Identification Program and releases Navy videos.
2020	United States	The Department of Defense formally releases three Navy UAP videos.
2020	Japan	The Defense Ministry announces a protocol for Self-Defense Force personnel who encounter unidentified objects (September).
2021	United States	ODNI publishes its preliminary UAP assessment: most of 144 reports remained unexplained for lack of data.
2022	United States	The All-domain Anomaly Resolution Office (AARO) is established.
2023	United States	A House Oversight subcommittee holds a public UAP hearing with former intelligence officer David Grusch and two Navy pilots. NASA’s independent UAP study team issues its report.
2023	Mexico	Mexico holds its first congressional UFO hearing (September), where alleged “non-human” remains are presented; scientists dispute the claims.
2024	United States	AARO publishes Volume 1 of its Historical Record Report, finding no verifiable evidence that the US government possessed extraterrestrial technology.

Missing something, or spotted an error? Tell us. Background: What is UAP? · How we label evidence