The Wow! Signal
A 72-second burst of radio energy that never came back.
On 15 August 1977, the Big Ear radio telescope at Ohio State University, scanning the sky for signs of extraterrestrial intelligence, recorded a strong, narrow-band signal near 1420 megahertz — the natural frequency of hydrogen. Volunteer astronomer Jerry Ehman circled the printout and wrote 'Wow!' beside it.
Loading the full dossier…
Connected dossiers
The Discovery of PulsarsContrast · A strange signal that was replicated and explained.
Europa's Hidden OceanSame open question · Searching for life beyond Earth.See The Wow! Signal in the discovery universe →
Ask the archive
Have a question about this dossier, or think a claim needs a better source? Send it to the editors.
How to read the labels
Hero image: The original Big Ear printout with Jerry Ehman's "Wow!" annotation. Image: Big Ear Radio Observatory and North American AstroPhysical Observatory (NAAPO) · Public domain · via Wikimedia Commons. Evidence labels describe the written claims, not the image. Version 1 · updated 2026-10-22.
