or Green Bank equation
Equation claimed to yield the number of technically advanced civilizations capable of interstellar communication in the Milky Way Galaxy as a function of several factors conducive to evolution of intelligent life with technological capabilities.
It was largely developed by Frank D. Drake (b. 1930) in 1961 at a SETI conference in Green Bank, W.Va. Of all the stars that form in the Galaxy, only some will give rise to life-supporting planets, and of those planets, only some will generate life capable of high technology and yet able to avoid technological destruction. Because the numbers for each factor are poorly known, the results generated vary from zero to millions.