Life's Chances: Are We Alone?

There are about billions of stars in our galaxy. But how would you even begin to estimate the odds of life?

In the 1960’s Frank Drake came up with a way of breaking the process in to pieces. Start with the number of stars. Then estimate the fraction of stars with planets. Then the fraction of planets that are earth-like. And so on.

Try it yourself. Use our Drake Equation interactive below to make your own estimate, and compare it against the estimates of others.

Drake Equation:
How many planets out there could support life? Use the Drake Equation to find out. Requires Macromedia Flash
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