We have just seen the first image of a black hole, the supermassive black hole in the galaxy M87 with a mass 6.5 billion times that of our sun. But what is that image really showing us?
This is an awesome paper on the topic by J.P. Luminet:
Image of a spherical black hole with thin accretion disk
Astronomy and Astrophysics, vol. 75, no. 1-2, May 1979, p. 228-235
Using my every day intuition I wondered: will we see the “shadow” of the black hole even if we’re looking edge on at the accretion disk? The answer is yes because the black hole warps space-time, so even if we wouldn’t normally be able to see the back of the accretion disk, we can in this case because its light is bent up and over the black hole. Similarly we can see light from the bottom of the back of the accretion disk because it’s bent under the bottom of the black hole. Plus there are additional images from light that does a half turn around the black hole leading to the inner rings.
What about the black hole “shadow” itself? Well initially I thought it can’t be an image of the event horizon because it’s so much bigger (2.6 times bigger). But if you trace back the rays, you find that for every point in the shadow, there is a corresponding ray that traces back to the event horizon. So in fact from our one observing location, we see all sides of the event horizon simultaneously! In fact infinitely many of these images, accounting for the virtually infinite number of times a photon can orbit the black hole before falling in. The edge of the shadow is due to the photon sphere – the radius at which light goes around in closed orbits. If a light ray coming in at an oblique angle just skims the photon sphere and then travels on to our telescopes, that is the closest ‘impact parameter’ possible, and it occurs at sqrt(27)/2*r_s
Huge thanks to:
Prof. Geraint Lewis
University of Sydney
Like him, I’m hoping (predicting?) we’ll see some moving images of black holes tomorrow
Prof. Rana Adhikari
Caltech
Riccardo Antonelli – for excellent images of black holes, simulations and ray-tracing code, check out:
The Event Horizon Telescope Collaboration
Check out their resources and get your local link for the livestream here:
Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme
Filming by Raquel Nuno
Animation by Maria Raykova
OK, just over an hour to go! This is the link to the Washington DC National Science Foundation livestream: https://ve42.co/NSFstream
Click here for links to other live streams (there are several available in different countries): https://ve42.co/EHTstream
0:28 nice pun
Take the amount of enjoyment you got out of it and divide it by 100. Now divide it by 100 again. Now divide it by a 100 a third time. That's how much enjoyment I got out of it. But I enjoyed your explanation of it.
I have a feeling someone sent you a sneak preview, Derek 😉
This duke from Venezuela is a pretty and smart
So you believe you can see your own back of your head! Interesting
The splash screen for this video had me thinking it would be about biathalon shooting technique.
I love this guys videos, but I don't know what's better; the content or his voice, his voice is so…. Satisfying 😍
Wow, i think i almost understood until the space and space time got bent^^
When you said light goes in a straight line, space time is bent, it kinda messed with my head lol
Exactly as I’ve predicted
So well done! I am excited about it as you are! Thanks!
If Jon Richardson and Adam Sandler had a kid.
there is something I can't understand … how the light was able to escape from the black hole when we took the photo … and something else … the black hole they said that shooted is far away so so much from us … the light should arrive us after billions and billions of years
Wow, this is new. Isaac Clarke lookalike from Dead Space franchise explaining Black Hole to me.
First of.. why is it Spherical if it's a HOLE? That doesn't fit the definition. 2nd. You use a made up mathematical pre-drawn image based on no physical empirical sizes and distances No One can verify to mimic the future picture of the black hole (which isn't even a real photo but made up of bits and bytes of radio data that in itself cannot be verified) and 3rd. you believe this reflects Reality? Dude, you are scientifically Bonkers!
This black hole is almost 55 millions light years away from Earth. So that means this image is 55 millions light years old?
Do we see the same image of the blackhole from every direction?
wow
great explanationIt's so weird to see the visual layout. It's almost as if the surface of the BH's sphere is displayed on a perpendicular, two dimensional plain, front and rear. I would love to know what happens to the acquired matter. If it isn't destroyed, and BH's aren't an immortal force, what happens to the matter that it took in? What is the ultimate structure of that particular information? Also, WHERE is it? If SpaceTime is distorted, then where is this information going? (i.e. Where is the singularity located as pertaining to SpaceTime location/region of space)
I'm sure that he just forgot to mention the fact that it is theorized that the image is of a Black Hole. Must have been oversight…LOL. The fact is that nothing is science fact …only theory according to Steven Hawkins "The Grand Design." In fact all of his books state that FACT. Some, however are more elegant than others. A elegant theory is testable, predictable and must match observation.
I'm just a the unquantified YouTuber, but I like to hear everyones ideas and keep an open mind, and never draw conclusions too quickly.
There is a branch of scientists that call themselves "Plasma Cosmologists." They say that the new image supports their theory that the source of the jets shooting from this supposed Black Hole, is actually a Super Plasmoid. A Super Plasmoid is a torus (donut) shaped magnetic anomaly with a glowing plasma around the center of the torus. That is what the image shows. A plasmid can be created in a lab and similar jets are created. This match the observation. I thought Black Holes don't let out light…hence the term Black Hole. Anyway "Wal Thornhil" of the "Thunderbolts Project" Youtube channel explains it quit simply without having to use infinity in his mathematics. It is very important that scientists tell people that not all scientists agree with that theory. By not mentioning that fact, they always look like they are trying to silence opposition. In science especially we need to hear from as many minds and ideas as possible. Who know what the the real truth of the image, but lets try not to draw conclusions too quickly. Here is a link to a good video. https://youtu.be/J4NffTr_GMk . It probably won't stay posted long.
Can you please make a video in which you explain the "ergosphere" of black holes in the same way?! Thank you.