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The Largest Black Hole in the Known Universe

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Re: The Largest Black Hole in the Known Universe

#11

Post by hyperliner »

Detrus wrote: post #8
hyperliner wrote: post #2

Here is the one thing that really keeps me awake at night: what if our science was the equivalent of a bunch of ants in a typical ant hill in anyone of our backyards, defining a mechanism or "method" through which they have explained for themselves the nature of the solar system? That's the one thing. And I can't shake it off.

What makes you think ants are so stupid? They farm, own slaves and have organized raids. Of course, the ones in your backyard typically don't do that. Those are like boring human villages.

I think they are very smart. They just don't really understand the solar system. And i think it is difficult for them to do.

Re: The Largest Black Hole in the Known Universe

#12

Post by hyperliner »

undershirt wrote: post #3
hyperliner wrote: post #2

Here is the one thing that really keeps me awake at night: what if our science was the equivalent of a bunch of ants in a typical ant hill in anyone of our backyards, defining a mechanism or "method" through which they have explained for themselves the nature of the solar system? That's the one thing. And I can't shake it off.

http://en.wikipedia.org/wiki/Epistemology

Useful. Thanks!

Re: The Largest Black Hole in the Known Universe

#13

Post by avar »

kghose wrote: post #10

Wow. In my memory, it was the pressure from the hot gases that kept a star from collapsing on itself. I did not know it was light pressure! Is this a typo in the article, or is it really light pressure holding up stars?

More specifically radiation pressure, not all of it is visible light. Some quick searching turns up http://en.wikipedia.org/wiki/Radiation_pressure#Stellar_inte... and http://www.astro.caltech.edu/~george/ay20/Ay20-Lec7x.pdf

Re: The Largest Black Hole in the Known Universe

#14

Post by gbog »

kabdib wrote: post #5

Nice article, but overuse of italics made me cut and paste into Emacs to read it.

Same here, except that in the end I didn't like the article. Medium is very fit for startup chatter and discussions on the relative merits of ios 8 and android 2.2. But writing about science in Medium, using this style and narrative? Not for me.

Re: The Largest Black Hole in the Known Universe

#15

Post by ggreer »

> While the ellipse that Mercury’s orbit makes around the Sun precesses at a rate of 43"-per-century due to relativistic effects (where 1° is 3600"), this smaller black hole should precess at 39°-per-orbit, and should inspiral in to the larger one in a timeframe of just a few thousand years!

In case anyone's curious: The double-quote is an arc-second. When measuring angles, a single quote is an arc-minute, which is 1/60th of a degree. An arc-second is, of course, 1/60th of an arc-minute. Rifle accuracy is measured in minutes of arc, with 1' being about an inch diameter circle at 100 meters. Proxima Centauri has a parallax of about 0.8".

To give you an idea of how far away Proxima Centauri is, we can scale everything down. A light-year is about 63,240 AU. A mile is 63,360 inches. So if Terra was an inch from Sol, Proxima Centauri would be about 4 miles away. The parallax from Proxima Centauri is the same as if you looked at an object 4 miles away, then moved your head 2 inches laterally. That's 0.8 arc-seconds. That's the second-closest star to us.

Re: The Largest Black Hole in the Known Universe

#16

Post by alixaxel »

It not the complete list: http://en.wikipedia.org/wiki/List_of_most_massive_black_hole...

On a related note, I never understood how a black hole (or frozen stars like the Russians call them) could potentially orbit or be swallowed by another black hole. If they "infinitely" deform space-time, shouldn't they be unable to move at all? If time stands still past the event horizon as they say and they also rip the space-time fabric so much, they shouldn't be able to "get out of the hole". This is just too mind-bogging for me I guess.

Re: The Largest Black Hole in the Known Universe

#17

Post by Sniffnoy »

alixaxel wrote: post #16

It not the complete list: http://en.wikipedia.org/wiki/List_of_most_massive_black_hole... On a related note, I never understood how a black hole (or frozen stars like the Russians call them) could potentially orbit or be swallowed by another black hole. If they "infinitely" deform space-time, shouldn't they be unable to move at all? If time stands still past the event horizon as they say and they also rip the space-t…

Also, according to that list, the central black hole of NGC 1277 is only 1/3 as large as claimed in the article, taking it out of contention entirely.

Re: The Largest Black Hole in the Known Universe

#18

Post by oakwhiz »

alixaxel wrote: post #16

It not the complete list: http://en.wikipedia.org/wiki/List_of_most_massive_black_hole... On a related note, I never understood how a black hole (or frozen stars like the Russians call them) could potentially orbit or be swallowed by another black hole. If they "infinitely" deform space-time, shouldn't they be unable to move at all? If time stands still past the event horizon as they say and they also rip the space-t…

What I would like to know is what happens when the two black holes collide.

Re: The Largest Black Hole in the Known Universe

#19

Post by kghose »

avar wrote: post #13
kghose wrote: post #10

Wow. In my memory, it was the pressure from the hot gases that kept a star from collapsing on itself. I did not know it was light pressure! Is this a typo in the article, or is it really light pressure holding up stars?

More specifically radiation pressure, not all of it is visible light. Some quick searching turns up http://en.wikipedia.org/wiki/Radiation_pressure#Stellar_inte... and http://www.astro.caltech.edu/~george/ay20/Ay20-Lec7x.pdf

And, from the wikipedia article:

"In the Sun, radiation pressure is still quite small when compared to the gas pressure. In the heaviest non-degenerate stars, radiation pressure is the dominant pressure component"

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