Comments on: NuSTAR catches a black hole’s hot belch

By: Joseph G

Joseph G — Fri, 26 Oct 2012 20:28:09 +0000

@40 Nigel Depledge: It’s definitely not for amateurs. Your arms have to exceed the speed of light on the upstroke, so it’s a pretty intense workout

By: Nigel Depledge

Nigel Depledge — Fri, 26 Oct 2012 13:57:43 +0000

Joseph G (39) said:

. . . Cygnus X-1 as the one “probable black hole”. And now we’re swimming in ‘em!

Erm, swimming in black holes?

How does that work? Do you have to use quantum-butterfly-stroke?

By: Joseph G

Joseph G — Fri, 26 Oct 2012 09:14:36 +0000

@ 36 Autumn: I remember being in 2nd grade or so and reading “How do We Know About Black Holes?”. It was very interesting, and didn’t dumb things down too much. Still, and this was less than 30 years ago, that book still held up Cygnus x-1 ( I believe I’m remembering that correctly, and it isn’t just a Rush song) as the best possible candidate for a black hole. I don’t recall that it even mentioned the possibility of an SMBH at the center of a galaxy.
Now we’re looking at one.
I love science.

Hehe, I remember that too. All the space books I had as a kid mentioned Cygnus X-1 as the one “probable black hole”. And now we’re swimming in ‘em! Not to mention a bunch of stuff that those books I grew up with never even hinted at, like the accelerating universe, and exoplanets.
I never knew Rush did a song about Cyg X-1. Awesome! Gonna fire up Grooveshark and see what I missed…

By: Nigel Depledge

Nigel Depledge — Fri, 26 Oct 2012 08:59:37 +0000

Autumn (36) said:

. . . Cygnus x-1 ( I believe I’m remembering that correctly, and it isn’t just a Rush song) as the best possible candidate for a black hole.

Yes, Cygnus X-ray source 1 (Cygnus X-1) was the first BH candidate identified.

And the Rush song was about the black hole that was suspected to be Cygnus X-1.

Six stars of the Northern Cross / In mourning for their sister passed / In a final flash of glory / Never more to grace the night,

(which is probably Bad Astronomy, as there is no reason to suppose any real relationship between the six bright stars of Cygnus and the Cygnus X-1 BH – does anyone know the distances to these stars and to the BH?)

And

I set a course just east of Lyra, / North-west of Pegasus, / Through into the light of Deneb, / Sailing ‘cross the Milky Way. / On my ship, the Rossinante (sp?), / Wheeling through the galaxy / Headed for the heart of Cygnus / Headlong into mystery.

By: Nigel Depledge

Nigel Depledge — Fri, 26 Oct 2012 08:52:45 +0000

@ Wzrd1 (33) -

Interesting additional info there.

Please note that the question I was answering was “does friction occur in gases?”. I was not attempting a complete explanation of how the accretion disc heats up. Although, reading my comment again, I can see that this was not explicitly clear first time around.

By: Autumn

Autumn — Fri, 26 Oct 2012 03:36:14 +0000

I remember being in 2nd grade or so and reading “How do We Know About Black Holes?”. It was very interesting, and didn’t dumb things down too much. Still, and this was less than 30 years ago, that book still held up Cygnus x-1 ( I believe I’m remembering that correctly, and it isn’t just a Rush song) as the best possible candidate for a black hole. I don’t recall that it even mentioned the possibility of an SMBH at the center of a galaxy.
Now we’re looking at one.
I love science.

By: Kenneth Polit

Kenneth Polit — Thu, 25 Oct 2012 23:08:58 +0000

This is so cool! I love this site, thanks, Phil.

By: Joseph G

Joseph G — Thu, 25 Oct 2012 22:01:15 +0000

@Wzrd1: Shoot, you can probably throw synchrotron and bremsstrahlung radiation in there too As usual, black holes defy simple explanations…

By: Wzrd1

Wzrd1 — Thu, 25 Oct 2012 20:24:15 +0000

Actually, the gas is warmed BOTH by friction AND irradiation by x-rays from the superheated gases closer in that are warmed from Van der Waal’s forces. There can also be magnetic components to emission from ions as well.
Let’s face it, a black hole is already complicated in and of itself, the accretion disk adds to the complicated environment.

By: Joseph G

Joseph G — Thu, 25 Oct 2012 19:57:13 +0000

@Nigel Depledge: Yes, because friction arises through Van der Waal’s forces, which can arise whenever two molecules or atoms get close enough to one another.

Ahh. I learned something today