The search for extraterrestrial intelligence: the programme of listening for artificial signals from other stars, begun by Frank Drake with Project Ozma at Green Bank in 1960 and continuous, in one form or another, ever since. The 1961 Green Bank meeting that followed produced the Drake Equation as an agenda for the discussion rather than as a prediction.
The institutional history
NASA funded a search until Congress cancelled it in 1993; the SETI Institute, founded in 1984, carried it privately, and Breakthrough Listen has funded large-scale surveys since 2015. The two results that matter to the record are opposite in kind: LGM-1, a repeating signal that turned out to be a pulsar and closed cleanly, and the Wow! Signal of 1977, which was never explained and never repeated.
Its relationship to the UAP question
SETI has historically kept the UFO question at arm’s length, on the ground that a signal is data and a sighting is testimony. That boundary has been argued about from both sides: Avi Loeb and the Galileo Project have pushed instrumented searches for objects rather than signals, and the criticism inside the alternative literature is that the boundary was institutional rather than epistemic. Both charges are worth holding at once.
Connections
Avi Loeb · Galileo Project · Project Galileo · Kardashev Scale · Directed Panspermia · SOL Foundation · Silurian Hypothesis · METI · Arecibo Message · Drake Equation · Wow! Signal · Fermi Paradox