Active Galactic Nuclei :
Black Holes Supersized
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
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.