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How likely there are alien civilizations (Drake Equation)

submitted by doogle

1 decade 5 years 10 months 3 weeks ago

Astronomer Ian Morison explains how scientists assess the likelihood of discovering extraterrestrial life, using a formula called the Drake Equation. (YT)

Complete video at: http://fora.tv/2008/04/03/The_Search_for_Extra-Terrestrial_Life