Nier Lecture/School of Physics and Astronomy Colloquium: James Kasting, Penn State

Title: The Search for Life in our Solar System and Beyond

Abstract: The drive to explore space is at least partly driven by the desire to discover whether life exists beyond the Earth. Exploration of planets and moons in our Solar System began in earnest several decades ago and has continued at a slow, but steady, pace since that time. The most likely venues are subsurface liquid water environments on Mars and on giant planet moons, but even Titan and Venus have caught astrobiologists' interest. The possibility that humans will visit Mars within the next 20 years makes this search even more exciting.

The best chance for actually finding life, however, may be on planets orbiting other stars. Telescopic observations from Hubble, Kepler, and now JWST have shown that exoplanets are abundant and that at least a few of these are potentially habitable. NASA's planned Habitable Worlds Observatory should allow us to find many more such habitable worlds and to search spectroscopically for signs of life, also hopefully within the next 20 years. So, the long-standing question, 'Are we alone?' may soon be answered.

Speaker Bio: James Kasting is an American geoscientist and Distinguished Professor of Geosciences at Penn State University. He is considered a world leader in the field of planetary habitability, assessing habitable zones around stars. He is interested in atmospheric evolution, planetary atmospheres and paleoclimates. Kasting writes about the geophysical history and status of the Earth, with a focus on atmospherics. He was well known among the geologists for his ground breaking idea on the only long term negative feedback for the atmospheric carbon dioxides: the carbon silica cycle.