Drake, Frank

Frank is Director of the SETI Institute's Center for the Study of Life in the Universe and Chairman Emeritus of the Board of SETI (Search for Extraterrestrial Intelligence), which he helped found. An Emeritus Professor of Astronomy and Astrophysics at the University of California at Santa Cruz, he made discoveries in radio astronomy (he was involved with the early work on pulsar stars) and works on the design of radio telescopes to monitor millions of frequencies simultaneously at very low costs. He is perhaps most famous for formulating the eponymous Drake Equation, which predicts the number of communicable civilizations in the galaxy. The Drake equation defines a set of concatenated probabilities— the average rate of star formation in our galaxy, the fraction of those stars that have planets, the average number of planets per star that can potentially support life, the fraction of those that actually go on to develop life at some point, the fraction of thse that actually go on to develop intelligent life, the fraction of civilizations that develop a technology that releases detectable signs of their existence into space, and the length of time such civilizations release detectable signals into space. The result of multiplying these probabilities is a constraint, or boundary, on the number of intelligent civilizations ('N'). Exemplifying our lack of information, the results of this sensitivity analysis, this probabilistic multiplication, varies so wildly that 'N' may lie anywhere between 1 (which would be us on earth alone) and >1,000,000.