The Drake Equation: Daniel Cowher

In 1961, Dr. Frank Drake from the National Radio Astronomy Observatory in Green Bank, West Virginia, envisioned a method to estimate how many civilizations with advanced forms of life exist in the Milky Way galaxy. His approach has come to be known as “the Drake equation”, and although developed simply as a means of estimation, the equation has prompted much controversy within the scientific community over the years. The equation is written as follows:

N = R* x f_p x n_e x f_l x f_i x f_c x L (explanation attached below)

Drake conceived his equation as a way to encourage dialogue at the first ever SETI (Search for Extraterrestrial Intelligence) meeting. Most people in the scientific community understand that the importance of the Drake equation is not to solve for an actual value of N, but rather to stimulate contemplation and research. The concept has been attributed a fair amount of popular interest and support, resulting in some continual funding of the SETI research. 

Further research into the Drake equation actually has some astronomers close to agreement on the product of the first three terms (R* x f_p x n_e). That said, the fractions related to life and intelligence are still largely based on conjecture. It’s these uncertain pieces to the question that have warranted harsh criticism about the equation. Science fiction author, Michael Crichton, describes this ambiguity saying, “the Drake equation can have any value from ‘billions and billions’ to zero…Speaking precisely [it] is literally meaningless”.

This idea posed by Dr. Frank Drake is very similar to Thales of Miletus questioning the origins of the universe. Drake himself knew very well that his first estimation of advanced civilizations in the galaxy would be tremendously off. But in doing so, he opened the doors to future scientists who would one day likely come to a much more accurate estimation. Drake succeeded in stimulating conversation about the topic, and in turn set the stage for further investigation on how to experimentally narrow in on a closer approximation.

(N is the number of civilizations in the Milky Way whose electromagnetic emissions are detectable. R* is the rate of formation of new stars. f_p is the fraction of those stars with planets. n_e is the number of planets suitable for life per solar system. f_l is the fraction of suitable planets where life occurs, f_i is the fraction of planets with life that develop intelligent life, f_c is the fraction of intelligent civilizations that develop space technology, and L is the length of time advanced civilizations emit signals into space.)

http://www.seti.org/drakeequation

https://www.cfa.harvard.edu/~scranmer/SPD/crichton.html