How far are Extraterrestrial Life and Intelligence after Kepler ?

Amri Wandel

doi:10.1016/j.actaastro.2016.12.008

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arXiv · 1612.03844

How far are Extraterrestrial Life and Intelligence after Kepler ?

Amri Wandel

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Abstract

The Kepler mission has shown that a significant fraction of all stars may have an Earth-size habitable planet. A dramatic support was the recent detection of Proxima Centauri b. Using a Drake-equation like 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 not very small, then a biotic planet may be expected within about 10 light years from Earth. Extending this analyses 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, Fc, and its average longevity. Assuming "optimistic" values for the Drake parameters, (Fb~Fc~1), and a broadcasting duration 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. Finally I calculate the distance and probability of detecting intelligent signals with present and future radio telescopes such as Arecibo and SKA and how it could constrain the Drake parameters.

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Amri Wandel. 2016-12-12. How far are Extraterrestrial Life and Intelligence after Kepler ?. https://doi.org/10.1016/j.actaastro.2016.12.008

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