From Cosmos:
Some scientists are convinced life is common in the universe, but intelligence rare. As for how long civilisations last - and stay detectable - few are willing to hazard a guess.
Two young physicists at Cornell University in upstate New York, Philip Morrison and Giuseppe Cocconi, had long been interested in gamma rays. One spring day in 1959, Cocconi posed an intriguing question: wouldn’t gamma rays be perfect for communication between the stars?
The discussion that followed led to a two-page article in the British journal Nature entitled “Searching for interstellar communications”. Sandwiched between a paper on the electronic prediction of swarming in bees and one on metabolic changes induced in red blood cells by X-rays, the duo argued that if advanced extraterrestrial civilisations existed, and wanted to communicate, they would likely use radio.
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