The Kepler mission has shown that a significant fraction of all stars may have an Earth-size habitable planet. Using a Drake-equation formalism I derive an equation for the abundance of biotic planets as a function of the relatively modest uncertainty in the astronomical data and of the (yet unknown) probability for the evolution of biotic life, Fb. I suggest that Fb may be estimated by future spectral observations of exoplanet biomarkers. It follows that if Fb is in the range 0.001 — 1 then a biotic planet may be expected within 10 - 100 light years from Earth. Extending this to advanced life I derive expressions for the distance to putative civilizations in terms of two additional Drake parameters - the probability for evolution of a civilization, F_c, and its average longevity. Assuming optimistic values for the Drake parameters, F_b~F_c~ 1, and a broadcasting longevity of a few thousand years, the likely distance to the nearest civilizations detectable by SETI is of the order of a few thousand light years. The probability of detecting intelligent signals with present and future radio telescopes is calculated as a function of the Drake parameters.
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