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Cool Active Galaxy Fact - Introduction

Active Galaxies

The central regions of active galaxies are now believed to contain very massive black holes. They probably range from a few thousand to a few billion times the mass of our Sun. These black holes grow by pulling in matter from the surrounding regions. This accretion is at the heart of the large energy emission we see from the galaxy. As matter falls toward a black hole, it will first be brought into orbit in a large disk around the hole. Then, just before it spirals into the hole itself, huge amounts of energy are released... beamed out in jets along the black hole's rotation axis. You can see these features in the artist's image of an AGN found on the top of the "Active Galaxies" page.


A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

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