How many intelligent civilizations should there be in our galaxy right now? In 1961, the US astrophysicist Frank Drake, who passed away on Sept. 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.

This places Drake in the company of towering physicists with equations named after them including James Clerk Maxwell and Erwin Schrödinger.

Unlike those, Drake's equation does not encapsulate a law of nature.

Instead it combines some poorly known probabilities into an informed estimate.

Whatever reasonable values you feed into the equation, it is hard to avoid the conclusion that we shouldn't be alone in the galaxy.

Drake remained a proponent and a supporter of the search for extraterrestrial life throughout his days, but has his equation really taught us anything?

Source

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.

This places Drake in the company of towering physicists with equations named after them including James Clerk Maxwell and Erwin Schrödinger.

Unlike those, Drake's equation does not encapsulate a law of nature.

Instead it combines some poorly known probabilities into an informed estimate.

Whatever reasonable values you feed into the equation, it is hard to avoid the conclusion that we shouldn't be alone in the galaxy.

Drake remained a proponent and a supporter of the search for extraterrestrial life throughout his days, but has his equation really taught us anything?

Source