The modern approach to the scientific exploration of intelligent life in the universe was pioneered in the early 1960s by Frank Drake and Carl Sagan in the US (1)and by Schklovskii and others in the USSR (2). It was based on a recapitulation of the physical parameters of astrophysics (primarily, planetary astrophysics based on our own solar system) and on extrapolations from our understanding of the biological structures(brains)that support consciousness. This resulted in the famous "Drake Equation"(3). It broadly assumed that the extant of civilizations where conscious, intelligent, life could be found would be proportional to the number of stellar systems, to the number of planets actually supporting “life”where such consciousness evolved, to the percentage of conscious entities on such worlds reaching a stage of intelligence recognizable as such(to us), to the percentage having developed means of interstellar communication(or generation of detectable electronic or other signals),and to the expected duration of such races’ existence in a form that transmitted a recognizable signal.
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