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- From the SETI Institute ...
-
- THE DRAKE EQUATION
-
- How can we estimate the number of technological civilizations that
- might exist among the stars? While working as a radio astronomer at
- the National Radio Astronomy Observatory in Green Bank, West Virginia,
- Dr. Frank Drake (now President of the SETI Institute) conceived an
- approach to bound the terms involved in estimating the number of
- technological civilizations that may exist in our galaxy. The Drake
- Equation, as it has come to be known, was first presented by Drake in
- 1961 and identifies specific factors thought to play a role in the
- development of such civilizations. Although there is no unique
- solution to this equation, it is a generally accepted tool used by the
- scientific community to examine these factors. The equation is usually
- written:
-
- N = R* x fp x ne x fl x fi x fc x L
-
- Where,
-
- N = The number of civilizations in The Milky Way Galaxy whose radio
- emissions are detectable
-
- R * = The rate of formation of stars suitable for the development of
- intelligent life
-
- f p = The fraction of those stars with planetary systems
-
- n e = The number of planets, per solar system, with an environment
- suitable for life
-
- f l = The fraction of suitable planets on which life actually appears
-
- f i = The fraction of life bearing planets on which intelligent life
- emerges
-
- f c = The fraction of civilizations that develop a technology that
- releases detectable signs of their existence into space
-
- L = The length of time such civilizations release detectable signals
- into space
-
- Within the limits of our existing technology, any practical search for
- distant intelligent life must necessarily be a search for some
- manifestation of a distant technology. A search for extraterrestrial
- radio signals has long been considered the most promising approach by
- the majority of the scientific community. Besides illuminating the
- factors involved in such a search, the Drake Equation is a simple,
- effective tool for stimulating intellectual curiosity about the
- universe around us, for helping us to understand that life as we know
- it is the end product of a natural, cosmic evolution, and for making
- us realize how much we are a part of that universe. A key goal of the
- SETI Institute is to further high quality research that will yield
- additional information related to any of the factors of this
- fascinating equation.
-
- - end -
-
-