Frank Drake has passed away but his equation for alien intelligence is more important than ever
How many intelligent civilizations should there be in our galaxy right now? In 1961, U.S. astrophysicist Frank Drake, who passed away on September 2 at the age of 92, came up with an equation to estimate this. The Drake equation, dating from a stage in his career when he was "too naive to be nervous" (as he later put it), has become famous and bears his name.