The Gravitational Universe

Shane L. Larson, Research Associate Professor, Northwestern University/Adler Planetarium

Of all the known forces of Nature, gravity plays a singularly important role in the Cosmos --- it is the only force that matters on the mind-bogglingly large scale of the entire Universe.  It drives the formation of star systems, it forces stars to ignite nuclear fires in their cores, it keeps galaxies bound together, and it tells the story of the beginning of the Cosmos as well as what it's ultimate fate might be. 

Our modern understanding of gravity is called General Relativity, described by Albert Einstein in 1915. One of the first major astronomical tests of general relativity was the observation of the total solar eclipse by Eddington on 29 May 1919. Since then, we have made remarkable discoveries that build on that early, first test of gravity. 

In this talk we'll revisit Eddington's observations and the role they played in cementing our understanding of gravity. We'll then leap forward a century, to the modern day, to talk about how a new kind of astronomy -- gravitational wave astronomy -- is transforming our understanding of the Cosmos, and the role that both professional and amateur astronomers are playing in opening our minds to the Gravitational Universe


Shane Larson is a research associate professor of physics at Northwestern University, where he is a member of CIERA (Center for Interdisciplinary Exploration and Research in Astrophysics). He is also an astronomer at the Adler Planetarium. 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 detectors for NASA. Shane grew up in eastern Oregon, and was an undergraduate at Oregon State University where he received his B.S. in Physics in 1991. He received an M.S. in Physics (1994) and a Ph.D. in theoretical physics (1999) from Montana State University. Before moving to Northwestern, he was a postdoctoral scholar at NASA's Jet Propulsion Laboratory, then at the California Institute of Technology, and finally at the Center for Gravitational Wave Physics at the Pennsylvania State University. He was formerly a tenured associate professor of physics at Utah State University. Shane is also an avid amateur astronomer, observing with two homebuilt Dobsonian telescopes, named EQUINOX and COSMOS MARINER. He currently lives in the Chicago area with his wife, daughter and three cats. In addition to astronomy, he enjoys hiking, mountain biking, and geocaching. He also collects Legos, fountain pens, and telescopes. He contributes regularly to a public science blog at, and tweets with the handle @sciencejedi .


Wednesday, August 16, 2017 - 13:45