Searching for Intelligence Among the Stars & the Drake Equation

At the quarterly meeting of the Board of Trustees of the SETI Institute (to which I have the privilege to belong), I spent some time this week with Dr. Frank Drake, the astronomer who is the father of the science of the search for extra-terrestrial intelligence (SETI). Now over 80, Frank is still going strong and very much involved with the ongoing quest to find evidence that there are other intelligent species among the stars.  Today, 52 years after Frank made the first search for possible intelligent radio signals from other star systems, our technology for searching has become much more sophisticated, although funding for the searches is still sporadic.

The discovery of so many planets orbiting other stars is very encouraging to those who hope to find our counterparts out there.  The Kepler mission is showing that planets the size of Earth and planets in the habitable zones of their own stars are more common than most astronomers had dared to hope.

A few years ago, I had the pleasure of encouraging Frank (and his coauthor Dava Sobel) to update a historical summary of how he came up with the "Drake Equation." Not so much an equation as a way of making estimates, this formula (which you can see behind him in the photo) is now taught in many introductory astronomy classes. It helps us summarize our best knowledge of astronomy, biology and sociology to figure out how common our type of technological civilization might be in the Galaxy.

Thanks to the Astronomical Society of the Pacific (which published the column,) you can read the story of how he came up with the equation by going to:
http://www.astrosociety.org/drake/index.html