What Is a Blazar? It’s Like Staring Down the Barrel of a Black Hole

Re:What Is a Blazar? It’s Like Staring Down the Barrel of a ... by mirimir on Friday July 13, 2018 @11:44PM (#17528681)

Could someone please ELI5 the distinction between blazars and quasars? I get that quasars are radio sources. But so are blazars, right? Is it that blazars are pointed right at us, whereas quasars aren't necessarily?

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Re:What Is a Blazar? It’s Like Staring Down the Barrel of a ... by teh_klev on Saturday July 14, 2018 @12:11AM (#17528781)

According to:

https://en.wikipedia.org/wiki/Quasar

In the 1980s, unified models were developed in which quasars were classified as a particular kind of active galaxy, and a consensus emerged that in many cases it is simply the viewing angle that distinguishes them from other active galaxies, such as blazars and radio galaxies.

..also...

A minority of quasars show strong radio emission, which is generated by jets of matter moving close to the speed of light. When viewed downward, these appear as blazars ...

To the best of my knowledge and interpretation they can be a type of "Quasar" but are really a type of galaxy with an active galactic nucleus (AGN) where their jets point towards Earth:

https://en.wikipedia.org/wiki/Blazar

A blazar is an active galactic nucleus with a relativistic jet (a jet composed of ionized matter traveling at nearly the speed of light) directed very nearly toward the Earth.

https://en.wikipedia.org/wiki/Active_galactic_nucleus#Types_...

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Re:What Is a Blazar? It’s Like Staring Down the Barrel of a ... by mirimir on Saturday July 14, 2018 @12:30AM (#17528830)

Thanks. I did skim the Wikipedia articles, but wasn't left with a clear understanding.

But OK, I get that they're all galaxies with AGNs aka massive black holes. And that blazars are the ones with a jet pointed right at us.

But now I'm curious. When a jet is pointed right at us, we see visible, x-ray and gamma radiation, and relativistic particles. But is longer wavelength radiation also emitted mainly on the jet axis?

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Re:What Is a Blazar? It’s Like Staring Down the Barrel of a ... by teh_klev on Saturday July 14, 2018 @01:00AM (#17528907)

I'd be a complete fraud if I said I could answer that :)

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Re:What Is a Blazar? It’s Like Staring Down the Barrel of a ... by mirimir on Saturday July 14, 2018 @01:50AM (#17529029)

Yeah, me too :)

But this is interesting: https://www.bu.edu/blazars/VLBAproject.html

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