  The search for a habitable extrasolar planet has long interested scientists,
but only recently have the tools become available to search for such planets.
In the past decades, the number of known extrasolar planets has ballooned into
the hundreds, and with it the expectation that the discovery of the first
Earth-like extrasolar planet is not far off. Here we develop a novel metric of
habitability for discovered planets, and use this to arrive at a prediction for
when the first habitable planet will be discovered. Using a bootstrap analysis
of currently discovered exoplanets, we predict the discovery of the first
Earth-like planet to be announced in the first half of 2011, with the likeliest
date being early May 2011. Our predictions, using only the properties of
previously discovered exoplanets, accord well with external estimates for the
discovery of the first potentially habitable extrasolar planet, and highlights
the the usefulness of predictive scientometric techniques to understand the
pace of scientific discovery in many fields.
