On September 14, 2015 the Advanced LIGO detectors measured gravitational waves for the first time. Gravitational waves, which are ripples in the fabric of space-time, are a fundamental prediction of Einstein's theory of General Relativity. The measurement of these particular gravitational waves told the story of their origin: two black holes, each the result of the death of a massive star, orbited each other at an increasing rate until they spiraled into each other and merged into a single black hole. In honor of this first measurement of gravitational waves, the 2017 Nobel Prize in Physics was awarded to three LIGO founders: Barry Barish, Kip Thorne and Rainer Weiss.
Since the first measurement, an additional 11 gravitational wave events have been confidently detected, along with an increasing number of candidate detections. Each new detection carries more information about the universe. Especially exciting was the gravitational wave from a pair of neutron stars (produced by stars not quite massive enough to form a black hole when they die) that was detected on August 17, 2017. The collision of the neutron stars produced not only gravitational waves but an explosion that was seen as a burst of gamma-rays (the most energetic form of light) as well as visible light measured by both the Hubble Space Telescope and many telescopes on earth. From this one event, astronomers learned that neutron star collisions produce many heavy elements and they were given a new way to calculate the expansion of the universe.
There is no registration or RSVP required for this event.
Howard Performing Arts Center, Andrews University, Berrien Springs, MI, 49104