active galaxies and quasars

Active galaxies

An Active Galaxy Nucleus (AGN) is a region in the centre of some galaxies which emits huge amounts of radiation.Not just visible light but also many waves from the rest of the electromagnetic spectrum including radio, infra red, ultra violet, x-ray and gamma rays.

It is thought that AGNs have super massive black holes at their centre. Matter close to this forms an accretion disk, a bit like a whirl pool, with matter spiralling inward at incredible speeds.This what causes radiation to be emitted. 

As the gas whirls into the black hole, a…