Does anyone know what drakes equation is?
(source: http://xkcd.com/384/) :rofl:
Seriously though, it's an equation that allows you to come up with an educated guess at the number of intelligent civilizations in our galaxy that we might be capable of communicating with, by breaking it down into factors that can be more easily estimated. For a more practical discussion, see e.g. http://en.wikipedia.org/wiki/Drake_equation
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