Are there civilizations out there listening? We don't yet know the answer, but Dr. Frank Drake, president
of the SETI Institute, came up with an equation that allows us to make an estimate by muliplying seven
quantities related to the prevalence of life. Since its introduction in 1961, this tool has come to be
known as the Drake Equation.
Use the Drake Equation to make your own estimate of the number of communicative civilizations in the Milky Way.
The great void in interstellar communication is not space, but time. In this animated presentation, learn how the lifetime of a civilization affects its ability to communicate.