Ask Dr. SETI ®
I read about the Drake Equation, but I find itīs pure guesswork to predict anything specific about the number of existing technological civilizations in our neighbourhood. I guess it is rather a matter of belief, and one guess can be about as good as another even if they ar wildly different. Am I completely wrong about that?
The Doctor Responds:
It is interesting that when the Equation was first written, the only factor which we had any basis to estimate with reasonable accuracy was the first, the rate of stellar formation. In the four decades since, we have learned something about extra-solar planets, so we can now estimate the second factor. We also have direct evidence as to the existence of two planets in their star's habitable zones, so (though the sample size is small) we can roughly estimate the third factor. At this rate, we should have three more factors nailed down by the middle of the next century! A value for the seventh will probably always elude us.
For the record, I consider the Drake Equation to be a marvelous tool for quantifying our ignorance. But in case you'd like to have a go at solving it, here's a downloadable spreadsheet which will let you plug in your own estimates for each of the seven factors, and see what results from your assumptions.
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this page last updated 28 December 2002
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