The S.E.T.I. [Search for Extra-Terrestrial Intelligence] Institute has been dedicated, since the
early 1980's, to searching the skies for evidence of intelligent life. At one time, it recieved
funding and support through NASA and Congress. These funds were cut in 1993 and since
then, the Institute has remained in the form of a non-profit organization and is headquartered
in Mountain View, California where it is privately funded.
Currently, S.E.T.I. is working on Project
Phoenix which is targeting Sun-like stars near to Earth from Arecibo, Puerto Rico. It is
currently the most comprehensive search for extra-terrestrial intelligence in the world. Project
Phoenix works by monitoring target stars on over two billion radio channels, and most of the
work is done by computers. However, when an interesting signal surfaces, astronomers are
called upon to decide what to do with it.
In addition to Project Phoenix, the Institute is working with the University of California at
Berkeley to build the Allen Telescope Array [ATA].
The ATA would allow astronomers to study up to several stars at once and on more than ten
billion radio frequencies. The ATA would be made available to S.E.T.I. astronomers to study
the sky 24 hours a day, 7 days a week. This monumental array should be completed in the
year 2005.
In 1961 Dr. Frank Drake, president of the SETI project and employee of the National Radio Astronomy Observatory in Green Bank, West Virginia created a mathematical equation which he hoped would answer the question - "Are we alone out here?"
N=N*fpnef1fifcfL
| N* | The number of stars in the Milky Way galaxy, multiplied by |
| fp | The fraction of those stars with planets, multiplied by |
| ne | The number of planets capable of supporting life, multiplied by |
| f1 | The fraction of planets capable of supporting life on which life actually does arise, multiplied by |
| fi | The fraction of planets where intelligent life evolves, multiplied by |
| fc | The fraction of planets with intelligent life that develops a technologically advanced civilization, multiplied by |
| fL | The fraction of time that a technically advanced civilization lasts. |
Unfortunately there are as many answers as there are stars, it depends on how optimistic or pessimistic you happen to be when you make the calculations. The equation has often been referred to as the "Glass of water" equation because no one can ever agree on the precise values for each of the variables. One thing that does seem certain is that we are definitely not alone.
Thank you to Andy for letting me use his S.E.T.I. image, and for letting me use the text
and HTML code for Dr. Drake's equation.
