Most images of black holes are illustrations. Here’s what our telescopes capture
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Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#2Source for the ring of fire image at the bottom of the page: http://eventhorizontelescope.org/simulations-gallery under "> Accretion Disk"
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#3Magnificent. I’ve been totally entranced by black holes since I first read A Brief History of Time as a kid. Years and years of trying to wrap my head around them, and they’re still just about the closest thing I get to a spiritual moment.
This is a fantastic piece, and even though some images are more visually striking, for me the ones that gives me the most chills are the time-lapse of stellar motion around Sagittarius A. Those are stars* being whipped around like toys. Stars. Over 97% of the mass of the solar system is just Sol, and these stars are more massive, and look at them move!
Chills.
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#4Keep in mind as well that no observation has yet distinguished between a neutron star and a black hole.
i.e. all those photos of super massive objects could be neutron stars, and we would not be able to tell the difference.
They are assumed to be black holes because of the mass, but if there is something in the law of physics that prevents black holes from forming we would not know.
We do not have a theory on quark degenerative pressure for example, which could possibly exert enough pressure to prevent black holes from forming (you would get quark stars instead, with no event horizon).
There are also time dilation issues that might make black holes impossible.
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#5If nothing can escape black holes how is it they “spew” things?
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#6Keep in mind as well that no observation has yet distinguished between a neutron star and a black hole. i.e. all those photos of super massive objects could be neutron stars, and we would not be able to tell the difference. They are assumed to be black holes because of the mass, but if there is something in the law of physics that prevents black holes from forming we would not know. We do not have a theory on quark d…
> all those photos of super massive objects could be neutron stars
Not if they are more massive than 2.7 times the mass of the Sun. That's the maximum mass for a neutron star (more precisely, it's the upper limit of the range of possible maximum masses, assuming the stiffest possible equation of state). Most of the objects referred to in the article are more massive than that, in some cases much more (the black hole at the center of our galaxy is about 3 million solar masses).
> We do not have a theory on quark degenerative pressure for example, which could possible exert enough pressure to prevent black holes from forming
No amount of pressure can prevent a black hole from forming, if the mass is large enough. Even for hypothetical quark matter, the equation of state can't get any stiffer than the assumed equation of state that leads to the 2.7 solar mass upper limit for neutron stars. Relativity sets limits to how much an object's pressure can resist gravity, regardless of the source of the pressure. That's where the maximum mass limit comes from.
> There are also time dilation issues that might make black holes impossible.
No, it doesn't. It just means that light signals from very near the horizon take a long time to get out.
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#7If nothing can escape black holes how is it they “spew” things?
The things aren't coming from inside the black hole. They're coming from a region near, but outside, the horizon.
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#8If nothing can escape black holes how is it they “spew” things?
The jets shown in the article come from the accretion disk [1], a disk of matter orbiting the black hole, formed as matter 'spirals' in.
For reasons we aren't 100% sure about yet (though we suspect it is due to angular momentum and energy transfer through some process [3]), matter (in the form of hot plasma) from this accretion disk can be launched out along the axis of rotation at relativistic speeds (close to the speed of light) in the form of astrophysical jets [2], which we can observe to due the radiation they emit. These jets play a large part in galaxy evolution, and as shown in the article can be huge, extending far beyond the galaxy itself.
1: https://en.wikipedia.org/wiki/Accretion_disk 2: https://en.wikipedia.org/wiki/Astrophysical_jet 3: https://link.springer.com/article/10.1007/s10509-009-9984-y
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#9Keep in mind as well that no observation has yet distinguished between a neutron star and a black hole. i.e. all those photos of super massive objects could be neutron stars, and we would not be able to tell the difference. They are assumed to be black holes because of the mass, but if there is something in the law of physics that prevents black holes from forming we would not know. We do not have a theory on quark d…
I think you’re confusing the lack of knowledge of whether or not singularities really form, with whether or not black holes form. There are very clearly black holes, but of course we can have no way of knowing if they contain singularities. Quark stars could exist, it not with the masses observed in Sag A*. Quark degeneracy pressure isn’t going to support the mass of millions, or even billions of suns. It might be that something other than a singularity is within the event horizon, but there will still be an event horizon. Given that, we’ll never observe the interior of a black hole and be able to communicate those findings, so it’s purely academic at that point.
As for time dilation... no. In no way could that magically overcome collapse.
Re: Most images of black holes are illustrations. Here’s what our telescopes capture
#10Keep in mind as well that no observation has yet distinguished between a neutron star and a black hole. i.e. all those photos of super massive objects could be neutron stars, and we would not be able to tell the difference. They are assumed to be black holes because of the mass, but if there is something in the law of physics that prevents black holes from forming we would not know. We do not have a theory on quark d…
> all those photos of super massive objects could be neutron stars Not if they are more massive than 2.7 times the mass of the Sun. That's the maximum mass for a neutron star (more precisely, it's the upper limit of the range of possible maximum masses, assuming the stiffest possible equation of state). Most of the objects referred to in the article are more massive than that, in some cases much more (the black hole…
> No amount of pressure can prevent a black hole from forming
And yet suns with far more mass than is needed to make a black hole exist. Because simple heat pressure keeps the black hole from forming.
Remember that the black hole doesn't just suddenly appear - to have enormous gravity the density must go up. If you prevent that from ever happening you can stop the black hole from ever starting in the first place.
You are talking assuming the black hole is already there, and saying quark degeneracy can't resist that, but you forget the black hole has to form first.
> No, it doesn't. It just means that light signals from very near the horizon take a long time to get out.
It also means mass takes a long (infinite) time to get in. So the black hole may never form.