Time: 3:30 PM – 5:00 PM
Location: Cole Auditorium, Greenwich Public Library, 101 West Putnam Avenue, Greenwich, CT.
Sunday, October 15, 2017, 3:30 pm
“How to see Black Holes” – Andrew MacFadyen – Associate Professor – NYU Center for Cosmology and Particle Physics
Black holes are now known to be abundant in the universe. Recently, merging binary black holes have been detected through their emission of gravitational waves by the LIGO detectors. I will discuss these black hole mergers and their supermassive cousins, with masses of billions of suns, and show supercomputer simulations of their interaction with surrounding interstellar gas.
These supermassive black hole binary mergers may soon be detected by studying pulsars in our galaxy and by future space missions such as LISA. These discoveries are transforming astronomy and ushering in the new age of gravitational wave astronomy with many more exciting discoveries expected in the future.
Andrew works on models of the explosive death of massive stars and on the growth of black holes from stellar collapse and at the centers of galaxies. He makes use of parallel computers to simulate the flow of gas in astrophysical environments where strong shock waves, ultra-relativistic speeds, and magnetic fields as well as neutrino emission and nuclear reactions are important.
Sunday, November 19, 2017, 3:30 pm
“Galactic Cannibalism” – Kathryn V. Johnston – Columbia University Department of Astronomy
Galaxies! Images of these objects are awe-inspiring – spirals of billions of stars, along with the gas and dust from which stars form, spinning slowly in the sky. Yet these majestic objects are thought to have formed quite violently through the agglomeration of smaller objects. Even our own home – the Milky Way galaxy – seems to be in the process of devouring several smaller galaxies! This talk examines why we think galaxies are cannibals in general, and what this means about the past and future evolution of the Milky Way in particular.
Professor Johnston received her Ph.D. in astronomy and astrophysics from UC-Santa Cruz. She was a member of the Institute for Advanced Study at Princeton, and then an assistant professor at Wesleyan University, where she was a recipient of an NSF CAREER Award. She joined the Columbia faculty in 2006.
Bowman Observatory Public Nights
First and third Wednesday of every month if skies are clear
October 4 & 18 – 7:30-9:30 PM
November 1 & 15 – 7-9 PM