
Simulation of what a massive black hole would look like - laurex
https://www.theweathernetwork.com/ca/news/article/nasa-black-hole-simulation-seems-to-def-reality
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djmips
Back in 1979, Jean-Pierre Luminet created the first "image" calculated the
using the IBM 7040 mainframe but drawn by hand plotting points on paper with
black India ink.

The pic is cool.

[https://www.engadget.com/2017/04/19/black-hole-image-jean-
pi...](https://www.engadget.com/2017/04/19/black-hole-image-jean-pierre-
luminet/)

~~~
jm4
Off topic, but that link doesn’t work because it redirects through
guce.advertising.com and I use a pi hole. I wonder if it was a deliberate
decision to redirect traffic away from the site to an ad server to have it
redirect back after trackers are set. Maybe they don’t care that they lost the
adblock users. Still, it seems like there’s a better way than to redirect all
traffic away. That makes no sense to me.

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robertony
It is intentional.

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BurnGpuBurn
The astronomical news community would do the public a very big favor if they
started stating clearly which pictures are taken by telescopes and which are
cgi.

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jcims
That and including a standard scale for apparent width.

I always thought that photos of other galaxies resolved into specks the size
of stars in the night sky. This composite of Andromeda and the moon blew my
mind:
[https://apod.nasa.gov/apod/ap061228.html](https://apod.nasa.gov/apod/ap061228.html)

~~~
sandworm101
But that isnt what you would see by eye or even a normal telescope. That is a
long-exposure image. By eye you can only see the brighter/smaller core. Get a
more sensitive camera, something able to see the diffuse gas and dimmer stars,
and andromeda would be twice even that size.

~~~
Fernicia
I don't think anyone is under the impression that image can be seen with the
naked eye.

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jcims
You're right! But I tried tonight just to see if it was possible to see
anything at all. My eyes are kind of shitty but we live out in the boonies
with no light pollution. There's a little 'yellow brick road' of stars that
lead you to it and if i looked slightly aside i could juuuuuuuuust make out
the slightest smudge where it is supposed to be. It was right on the edge of
my ability to perceive it, need to try again after spending an hour in the
dark.

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sudhirj
There's a clearer explanation of why the disk looks that way and how the
gravitational warp makes those light paths
[https://www.youtube.com/watch?v=zUyH3XhpLTo](https://www.youtube.com/watch?v=zUyH3XhpLTo)

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mcv
Awesome, but also oddly familiar. Does this new simulation add anything to Kip
Thorne's black hole simulation[0] as soon in Christopher Nolan's movie
_Interstellar_?

[0] [https://www.wired.com/wp-
content/uploads/2014/10/ut_interste...](https://www.wired.com/wp-
content/uploads/2014/10/ut_interstellarOpener_f.png)

~~~
SiempreViernes
Not really, they are both the same sort of pop-cultural prop. I think one does
include a bit of the blue shifting effects of the disk, a prominent effect
they left out of interstellar.

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nobrains
There were 2 major events when this became to regular people who were
interested in black holes. First was the Interstellar movie, and the second
was the black hole picture by the Event Horizon telescope team. This
independent simulation also comes to the same conclusion. In summary, the
light from the side of the black hole facing away from us, is also curved back
and thrown towards us, when looking at the black hole from the side.

~~~
thwarted
_the light from the side of the black hole facing away from us, is also curved
back and thrown towards us, when looking at the black hole from the side_

What does it mean to look at a black hole "from the side"?

~~~
caf
Perpendicular to its spin axis (black holes have angular momentum, which is a
vector).

~~~
mr_toad
Does the ‘equator’ of a spinning black hole have any relationship or influence
on the accretion disc? Or vice versa?

Is the direction of spin of a black hole even knowable?

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caf
The spinning black hole drags space around it, which certainly distorts the
accretion disc.

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ijidak
Well, I guess Nolan got it right. I seem to remember that being how the black
hole was depicted in Interstellar

~~~
RiceMunk
If I remember correctly Nolan consulted with some actual astrophysicists to
get it right. Furthermore, they managed to make use of the Hollywood-funded
super computer time to get some actual science out of the deal. Here's a
random article I googled discussing the topic:
[https://www.wired.com/2014/10/astrophysics-interstellar-
blac...](https://www.wired.com/2014/10/astrophysics-interstellar-black-hole/)

~~~
mr_mitm
Not just any astrophysicist. It was Kip Thorne, who was already an authority
in general relativity even before he received the Nobel prize in 2017 for his
work on gravitational waves. His works on the movie led to the publication of
a scientific paper:
[https://aapt.scitation.org/doi/10.1119/1.4916949](https://aapt.scitation.org/doi/10.1119/1.4916949)

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smcameron
There are some nice somewhat interactive black hole renderings on shadertoy...

[https://www.shadertoy.com/results?query=black+hole](https://www.shadertoy.com/results?query=black+hole)
[https://www.shadertoy.com/view/XdjXDy](https://www.shadertoy.com/view/XdjXDy)

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grawprog
The simulation is pretty amazing, but the wording and headline of the article
point to what I feel like in science, not just physics, ecology's pretty bad
for it too, but the impression I always get from models and simulations is
that when they don't match up with reality, somehow reality's wrong and not
the model or simulation.

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tempguy9999
"Mind-bending black hole simulation appears to defy reality"

"Appears to". Doesn't say it does. Doesn't suggest it does. I think you're
being unfair.

> when they don't match up with reality, somehow reality's wrong and not the
> model or simulation.

Can you point to some examples? This is not something I've noticed myself.

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rsj_hn
Lovely. Interestingly, this feature of black holes that they allow you to see
what is on the "far side" of the black hole as a result of gravitational
lensing was one of the heuristics used by Leonard Susskind to propose the
holographic principle in his famous paper, "The World As A Hologram"
[https://arxiv.org/abs/hep-th/9409089](https://arxiv.org/abs/hep-th/9409089)

Note especially Figure 2, Figure 3, Figure 4, used to justify that a two
dimensional screen is enough to capture all the information.

Obviously there is a lot more going on -- especially the black hole entropy
formula which says that entropy growths with surface area not volume -- to
motivate this idea, but I always thought those figures were particularly
educational.

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gigatexal
Click-bait title, ugh. “The universe is under no obligation to make sense to
you.” - Neil DeGrasse-Tyson

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sova
Veritasium made an excellent youtube video explaining how this effect works
(before the image was released!)
[https://www.youtube.com/watch?v=zUyH3XhpLTo](https://www.youtube.com/watch?v=zUyH3XhpLTo)

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Gormisdomai
Also interesting in this image is that the left side of the disk around the
black hole appears brighter than the right side, because the matter in the
disk is spinning so fast that you get Doppler beaming near to the speed of
light.

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bufo
Here's a real time raytracer I wrote with first person movement to move around
the black hole:
[https://www.youtube.com/watch?v=jDqnRs_xTWQ&feature=youtu.be](https://www.youtube.com/watch?v=jDqnRs_xTWQ&feature=youtu.be)
[https://github.com/fernand/schwarzschild_raytracer](https://github.com/fernand/schwarzschild_raytracer)

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rezlhonep
There was a cooler ESA simulation a few months back. I’ve struggled to try and
find the video

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SiempreViernes
Maybe you think of this _magnetohydrodynamic simulation_ :
[https://www.eso.org/public/videos/eso1907o/](https://www.eso.org/public/videos/eso1907o/)

The NASA video is a visualisation that "simulates" the optical distortion.

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GistNoesis
The picture is beautiful but I feel that it doesn't convey the right mental
model of the black hole.

It would be a great picture to illustrate gravitational lensing, but it's a
not so great one for conveying what a black hole is.

From the picture it seems that particles are swirling around in multiple
directions, whereas the mental picture you should get is : there is a standard
accretion ring but with gravitational lensing visual filter turned on.

A black Saturn with a Snapchat filter

~~~
mcv
A black Saturn wouldn't do it justice. Saturn doesn't bend space as extremely
as a block hole does, and it's that extreme bending of space that's the hard
part to visualise about a black hole. It's trivial to imagine a black ball
with a ring around it, but it's the bending of space and the subsequent
bending of light that's the hard part.

~~~
GistNoesis
Yep bending of light and warping is hard to visualize. Thankfully we can play
with our own black hole at home. I took my crystal ball cut some cardboard
into a ring.

If you look, you can see both side of the ring behind the black hole :

[https://gistnoesis.github.io/blackhole.jpg](https://gistnoesis.github.io/blackhole.jpg)

You just need to imagine a little stronger warping.

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egfx
Interesting. I’m amazed how the shape was declared by the notion you would
never lose “sight” of the black hole no matter the direction you looked at it
from. I just realized that was how the shape came to be.

~~~
lisper
> you would never lose “sight” of the black hole

You would never lose sight of the _accretion disk_. And you can see both sides
simultaneously.

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wallace_f
Would it be possible that a habitable planet be close enough to one to see
this with ordinary telescopes?

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SiempreViernes
Might be, black holes come in a very large range of sizes so a configuration
where you have a habitable planet very close to a large enough black hole
isn't impossible.

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agumonkey
isn't the gravity bending effect used by astronomers to compute stuff hidden
by planets too ?

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arianvanp
Yes! E.g. you can use the sun as a lens during a solar eclipse. It was
actually the experiment that proved Einstein's general relativity to be more
than a theory, because during a solar eclipse we can see stars at the edge of
the eclipse that are actually _behind_ the sun.

[https://en.wikipedia.org/wiki/Solar_eclipse_of_May_29,_1919](https://en.wikipedia.org/wiki/Solar_eclipse_of_May_29,_1919)

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etxm
That’s beautiful.

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andywenkhh
This reminds me of the black hole shown in Interstellar (movie). It's
fantastic even though being in a shelf is kind of unbelievable ;-)

