The Drake Equation and habitable planets

  • Monte Ross
Part of the Springer Praxis Books book series (PRAXIS)


In 1960 Frank Drake devised an equation which expressed the number of intelligent communicating civilizations in the galaxy as the product of a number of probability factors, viz: N = N* fp ne fl fi fc fL where: N* is the number of stars in the galaxy fp is the fraction of stars that host planets ne is the number of planets per star capable of sustaining life fl is the fraction of planets in ne on which life evolves fi is the fraction of fl that evolves intelligence fc is the fraction of fi that communicate fL is the fraction of the planet’s life during which the civilization actively communicates.


Main Sequence Astronomical Unit Habitable Zone Parent Star Advanced Civilization 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Praxis Publishing Ltd. 2009

Authors and Affiliations

  • Monte Ross
    • 1
  1. 1.Laser Space Signal ObservatoryOlivetteUSA

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