Unveiling the first-ever image of a black hole [video]

[JumpCrisscross]

Good video that correctly predicted the image and describes why it looks the way it does [1].

TL; DR The dark area is the entire surface of the event horizon, including the side facing away from us, plus some more due to photons missing the event horizon "directly" being drawn in. One side is brighter due to its being Doppler boosted.

[1] https://www.youtube.com/watch?v=zUyH3XhpLTo

[piker]

Higher resolution official release seems to be: https://www.nsf.gov/news/special_reports/blackholes/download...

[turshija]

Related video, made by Veritasium yesterday, is one of my favorite videos in a long time. He explained how the prediction of this image was made (before the image got released) and the video is great and fun to watch.

https://www.youtube.com/watch?v=zUyH3XhpLTo

[a_d]

Previous work on this was done for the movie Interstellar. The resolution of the rendering software was so high that team members were able to examine the black hole very closely - Because Gargantua was spinning at almost the speed of light, the rendering showed that spacetime warped into shapes never seen before. This led to the publication of —> https://arxiv.org/abs/1502.03808

Kip Thorne describes his work not this in a book called the science of interstellar.

Kip’s description of black holes here is also fascinating: https://youtu.be/oj1AfkPQa6M — first time I learnt what “warped” space-time means :)

[yaseer]

International collaboration on scientific projects (International space station, CERN) always fills me with hope and optimism for humanity.

It's a nice contrast to opening the papers and reading the regular news, dominated by politics, with all the pessimism that creates.

Hooray for science.

[okket]

The papers with the scientific details are here (open access):

https://iopscience.iop.org/journal/2041-8205/page/Focus_on_E...

Article in physics world with comparisons to simulations:

https://physicsworld.com/a/first-images-of-a-black-hole-unve...

"AskScience" AMA on Reddit about the breakthrough:

https://www.reddit.com/r/askscience/comments/bbknik/askscien...

[jjeaff]

I am not trying to throw cold water on this, but I have some questions.

This ted talk has a very basic explanation of how they constructed this image. I was curious if anyone with image interpolation experience could weigh in on the method. https://www.youtube.com/watch?v=P7n2rYt9wfU

When she first starts explaining their method around 8:00m in, I was initially very skeptical of this result because she said that they feed images of what we "think" a black hole should look like and use algorithms to compare the captured data with those images.

She then goes into explaining the measure they take to keep the resulting image from being biased by passing environmental images and images of other astronomical anomaly to make sure that those images return similar results.

But I can't for the life of me figure out how passing non-stellar imagery could return something similar. And if it does, why do we need to feed it an example of what we think it should look like at all?

[itake]

This 9 min video [0] does an excellent job explaining what we are looking at.

[0] - https://www.youtube.com/watch?v=zUyH3XhpLTo&feature=youtu.be

[kristofferR]

The US unveiling is WAY better than the EU unveiling that is linked to above. They have images, animations and graphs that's easily understandable by the layperson, and it's scientists instead of politicians speaking.

https://www.youtube.com/watch?v=2DxjuE7WDlk

They talk about how the image was produced, and how they made such a small image out of the 5 PetaByte of data they gathered from stations all over the world.

[AnimalMuppet]

One of the cool things about this was that the data was too large to ship over the internet (in a reasonable amount of time). They actually shipped physical disks full of data.

Even today, never underestimate the bandwidth of a station wagon full of disks...

[r721]

"This is more realistic of the uncertainties involved in this high-end image reconstruction. Still amazing though! Fig. 4 in https://iopscience.iop.org/article/10.3847/2041-8213/ab0e85 "

https://twitter.com/karlglazebrook/status/111598136971105894...

[symlock]

For those wondering how the image was constructed: https://www.youtube.com/watch?v=hMsNd1W_lmE

Basically, the image has been constructed by calculations on massive measurement data-sets from multiple synchronized telescopes around the world.

So this isn't a "photo" in the normal sense. It's a reconstruction of many, many radio waves.

[nonbel]

It doesn't sound like they just snapped a picture. The one guy says they used "supercomputers" for 6 months to get the image.

Sunspots look black relative to the rest of the sun but are actually very bright. Could this be the same thing? How did they set the black level? Is there a description of the procedure somewhere?

EDIT:

Found the paper describing the data processing: https://iopscience.iop.org/article/10.3847/2041-8213/ab0c57

[_void]

I don't get the whole "oh it's too blurry and nothing is visible" comments. It's a black hole, what did you expect to see? Interstellar CGI?

[montenegrohugo]

It's just a stupid collection of small pixels but somehow it feels very overwhelming looking at it for the first time.

What a time to be alive

[novaRom]

Excellent example of successful international collaboration, with distributed team. Great results and promising future work: they say Sagitarius-A* is their next target!

[niklasrde]

The telescope's announcement is up, too: https://eventhorizontelescope.org/

[ckugblenu]

The EU is finally learning from the US when it comes making a lot of fanfare for discoveries and other inventions.

[huffmsa]

So is a black hole 3 dimensional? Is it a sphere? Or does it only work in certain directions? Does everything "fall" the same direction?

I ask because even in a brief history of time, the diagrams are very "single plane of space-time, pulled infinitely deep by the black hole"

[alkonaut]

So much higher res than I thought (I was expecting a 3x3px black and white).

Does anyone know if this is aggregated over a long time so it's unlikely to improve with more observation? And what is limiting the resolution at this point?

[veryworried]

Is this what we would see with the naked eye if we were close enough to the black hole? Or would we see nothing, because at this distance we would be dead (or the universe ended all around us)?

[e0m]

"This is like viewing a mustard seed in Washington DC from Brussels"

[negamax]

Does anyone remember Interstellar. Their black hole simulation was based on hard science. Looks fairly similar

[dugluak]

Why did they choose this very distant galaxy? why not something that's close to us like the andromeda galaxy or even the center of our own galaxy?

[zakki]

Is black hole a 3D object like a sun? If so, I assume the light in the event horizon cover the whole object, i mean 3D shaped as well. How the picture taken from the telescope shown the dark area where the black hole is located? I mean, shouldn’t the whole black hole covered by the light thus we can’t see the black hole?

[zeristor]

How big a VLBI baseline would they need to see much more detail? Are there any plans for a space based VLBI; not easy when you consider the utterly huge amounts of information they have to transfer, a radio telescope in a L5 would be a start.

Also I'd be interested to read how they got around scintallation of the Interstellar Medium.

[mythz]

Katie Bouman herself did a fascinating Ted Talk behind the effort involved for creating the first image of a black hole:

https://www.ted.com/talks/katie_bouman_what_does_a_black_hol...

[Aardwolf]

So we got an image of one in a far away galaxy before the one in the center of our own galaxy!

[ArtWomb]

Breakthrough discovery in astronomy: press conference

https://www.youtube.com/watch?v=Dr20f19czeE