Active Galactic Nuclei :
Black Holes Supersized

Wayne Clark,
St. Louis Astonomical Society

Wayne Clark of the Saint Louis Astronomical Society, will be featured at the May meeting of the Society.

A galaxy is an immense collection of billions to perhaps a trillion stars, held together by the pull of gravity. Our Sun is a resident of one - the Milky Way galaxy. There are billions of galaxies strewn through the observable universe. While the Milky Way’s center is relatively well behaved, there are many galaxies whose centers spew out fountains of high energy radiation. The energy sources for these active galactic nuclei are almost certainly black holes. Each of these central black holes contains a quantity of matter equivalent to thousands or millions of Suns, and so they are called supermassive black holes. Mr. Clark will discuss the different kinds of active galaxies observed - Seyfert galaxies, quasars, blazars and others - and explain the links between them and the supermassive black holes lurking in their cores.

Wayne Clark, an Astronomical Society member for over three decades, is an active amateur astronomer and astrophotographer. He recently attended a NASA workshop on advances in high energy astrophysics that provided information and images about active galactic nuclei.