CONCEPT
Drake Equation
Frank Drake's 1961 formalization of the variables governing the likely number of technological civilizations in the galaxy — the founding scientific question that made SETI possible.
The Drake equation, formulated by Frank Drake in 1961 for the Green Bank conference that founded modern SETI, multiplies together the variables that determine how many communicating civilizations might exist in the galaxy: the rate of star formation, the fraction of stars with planets, the fraction of those planets capable of supporting life, the fraction on which life actually develops, the fraction on which intelligence evolves, the fraction of intelligent species that develop communication technology, and the fraction of a civilization's lifetime during which it is communicating. The equation's power lies not in specific numerical answers — many of the factors remain poorly constrained — but in its demonstration that the question of other minds can be broken down into empirically addressable components.
