Raphael Gobat - 2nd Talk - The habitability of galaxies through time

Abstract: The idea of a plurality of worlds, in which the Universe is filled with a vast number of life-harboring planets similar to our own, has long fascinated philosophers and has more recently become part of popular culture. This idea was entirely speculative and remains unproven, as to this day no incontrovertibly habitable planet other than our own has been found. However, the rapid pace of exoplanet discoveries and the large amount of detected extrasolar planets has made the determination of true planetary distributions functions possible. Furthermore, our knowledge of the evolution of galaxies and their stellar populations is now mature enough that we can model their formation history from early times to the present day. Combining the two, then, allows us to estimate the amount of potentially habitable planets in our galaxy and others.