SETI and the Search

The Search for Extraterrestrial Intelligence (SETI) has scanned the sky for alien radio signals since 1960. The Wow! signal of 1977 remains the most intriguing candidate — a strong narrowband signal from the direction of Sagittarius that lasted 72 seconds and has never been detected again. No confirmed alien signal has ever been found.

Modern SETI has expanded beyond radio. Scientists look for laser pulses, anomalous stellar dimming patterns (like Tabby's Star), artificial atmospheric pollutants on exoplanets, and even megastructures like Dyson spheres.