USAF detected radio emission from the Crab Pulsar

Steinn has a nice summary of the strange-but-true story: the Air Force almost beat astronomers to the discovery of Pulsars in 1967.

Quick summary: An Air Force radar operator in Alaska in 1967 named Charles Schisler noticed a fluctuating radio source. As a former navigator, he recognized that, because it appeared 4 min earlier each day, it must be a celestial source. He noted its position as in Taurus, and took careful notes of source strength and position. His superiors told him not to pursue it. A year later, Bell & Hewish discovered it was pulsating like clockwork, Nobel Prize, yadda yadda.


Go read Steinn's summary + the more useful comments.