The Drake Equation

How many people are familiar with the famous Drake Equation?

The equation states:

• factor R* is the mean rate of star formation in the Galaxy;
• fp the fraction of stars with planetary systems;
• ne the number of planets in such systems that are ecologically suitable for the origin of life;
• fl the fraction of such planets on which life in fact develops;
• fi the fraction of such planets on which life evolves to an intelligent form;
• fc the fraction of such worlds in which the intelligent life form invents high technology capable at least of interstellar radio communication;
• L is the average lifetime of such advanced civilizations.

Alot of if’s.

Plug in your values for each term, multiply them together, and you’ll get a number for N: the number of detectable civilizations in the Milky Way…

(Frank Drake’s) value for N is, and he’ll say it changes each time he thinks about it. But in general, he says with a wink, the number is likely between one and a billion, maybe around 10,000.

Well, we know it is for sure one.

Astronomers have also estimated the universe to be approximately 13.8 billion years old.

If we take off 3.8 billion years from the big bang (to allow the universe to form) to when we can start to fill in the equation, that means each of those 10K possible advanced civilizations could last 10 million years each and never overlap each other.