Step away, for an hour, from Earth’s problems to contemplate if we really are alone in the great cosmic darkness. We are the first humans to know with certainty that there are planets orbiting other stars. Is ours the only one to harbor life? If not, what sort of alien life forms might there be, and how are we to find them? Astronomer Shane Larson returns for another dazzling slide lecture, this one to consider the equally staggering possibilities that life exists elsewhere or that it does not.

Professor Larson is a research associate professor of physics at Northwestern University, where he is the associate director of CIERA (Center for Interdisciplinary Exploration and Research in Astrophysics). He works in the field of gravitational wave astrophysics, specializing in studies of compact stars, binaries, and the galaxy.  He works in gravitational wave astronomy with both the ground-based LIGO project, and future space-based observatory LISA. He was formerly a tenured associate professor of physics at Utah State University. He is an award winning teacher, and a Fellow of the American Physical Society. He contributes regularly to a public science blog at writescience.wordpress.com, and tweets with the handle @sciencejedi.