Tau.Neutrino said:
Gigantic dusty donut around a black hole imaged for the first time
What do radio galaxies, quasars, blazars, Seyfert galaxies and active galactic nuclei all have in common? Everything, it turns out: These are all different names for the same celestial objects viewed from different angles. Now, for the first time astronomers have directly imaged the last piece of the puzzle that ties them all together – a dusty donut of material that surrounds a supermassive black hole.
more…
Third time I think. But first time when the black hole is in another galaxy.
> What do radio galaxies, quasars, blazars, Seyfert galaxies and active galactic nuclei all have in common? Everything.
> These objects are all known broadly as active galactic nuclei (AGN), but somewhat confusingly they go by many different names, depending on how they look from here on Earth. The brightest AGN are called quasars, while blazars are those with a jet that just happens to be pointing directly at us. Seyfert galaxies are basically quasars with visible host galaxies, while radio galaxies are particularly loud at radio frequencies.
Yep. I haven’t seen it that neatly explained before.
> Cygnus A
Good choice.
> the torus came into focus as a clumpy cloud of dust with a radius of a whopping 900 light-years
That’s no good. In order to drive the AGN, a torus has to be very much closer than that. Unless I’m mistaken.