what is the essential difference between an ordinary galaxy and an active galaxy?

Answer 1

Hi Astro

An active galaxy is defined as one which contains an active galactic nucleus (AGN). The current most popular model for AGNs is that they are powered by accretion onto central supermassive black holes. Hot accretion discs peak in the UV, but radiate across most of the spectrum. Additional processes result in jetting and in emission of high energy X-rays.

Active galaxies include Seyfert galaxies, quasars (QSOs), radio galaxies and blazars. Their "activity" is characterised by the emission levels corresponding to the activity of the central accretion disc. Non active galaxies have low emissions corresponding to relatively low activity central black holes.


Hope this helps!
The Chicken

Answer 2

An lively galaxy isn't pronounced as that, you're touching on a galaxy with an lively Galactic Nucleus. this could be a galaxy whose critical center is brighter and greater lively in any respect wavelengths than galaxies with non-lively galactic nuclei. counting on our perspective of view, an AGN might desire to be labelled a Seyfert galaxy, a quasary, or a burstar. All 3 are basically distinctive manifestations of the comparable subject. Scientists have faith that AGNs are the effect of large-vast black holes in a feeding frenzy in that galaxy. The interest we see is as a results of severe gamma rays and xrays, and frequently radio jets of cloth and plasm ejected from the middle alongside the rotational axis at close to easy-speeds.

Answer 3

Hi. By active I think you mean giving off lots of energy because they are ALL active. Usually this is caused by a large black hole or something just as strange at the center pulling in matter and emitting a lot of light as a result.