Caelum Incognitum — The interactive encyclopedia of ufology
Pulsar CP 1919 (“LGM-1”)
Astronomy, exobiology & SETI
In 1967, at Cambridge, a radio signal of extreme regularity (one pulse every 1.33 s) was first nicknamed “LGM-1” for “Little Green Men”. It was the first pulsar, a rotating neutron star. The episode remains the model of apparently artificial signals explained by physics.