Methodology and sources

What is included and what is not

Included: state agencies with a mandate over the phenomenon (SEFAA and DGAC in Chile, CEFAE in Argentina, GEIPAN in France, the Aeronautica Militare in Italy, AARO and NARA in the United States, The National Archives in the United Kingdom, the Arquivo Nacional in Brazil, the Ministry of Defence in Spain, the Office of the Chief Science Advisor in Canada), peer-reviewed academic publications, open scientific repositories, and established press when reporting verifiable facts with attribution.

Not included: forums, social media, speculation channels, material without an identifiable source, or forwarded chains. No content reaches this site automatically: every section goes through editorial review, and press reports must additionally clear a relevance threshold and not repeat a story already published.

How it works

A purpose-built system queries 26 sources continuously, records each new document with its origin, date and permanent link, and weights it against objective indicators: proximity to sensitive installations, the existence of instrumental records (radar, infrared), declassified status, and the presence of qualified witnesses. The weighting orders the review; it does not replace editorial judgement.

Known biases

An archive is only as good as what survived. The British Ministry of Defence systematically destroyed its files on the subject every five years until 1967, so most material predating that date is lost. Australia mislaid the bulk of its military archives on the matter. The density of recent cases is therefore artificially higher than that of the early decades: it does not necessarily reflect an increase in the phenomenon, but in its preservation.

Terminology

This archive uses UAP (Unidentified Anomalous Phenomena) and its Spanish equivalent FANI, the term used by Spanish-speaking official bodies. It is what was popularly called a UFO for decades; that word is kept only where the cited source uses it. The distinction is not cosmetic: describing something as unidentified implies no hypothesis whatsoever about its origin.