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The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was designed to capture images of a black hole. Today, in coordinated press conferences across the globe, EHT researchers reveal that they have succeeded, unveiling the first direct visual evidence of a supermassive black hole and its shadow.
This breakthrough was announced today in a series of six papers published in a special issue of The Astrophysical Journal Letters. The image reveals the black hole at the center of Messier 87, a massive galaxy in the nearby Virgo galaxy cluster. This black hole resides 55 million light-years from Earth and has a mass 6.5 billion times that of the Sun.
The EHT links telescopes around the globe to form an Earth-sized virtual telescope with unprecedented sensitivity and resolution. The EHT is the result of years of international collaboration, and offers scientists a new way to study the most extreme objects in the Universe predicted by Einstein's general relativity during the centennial year of the historic experiment that first confirmed the theory.
[...] This research was presented in a series of six papers published today in a special issue of The Astrophysical Journal Letters, along with a Focus Issue:
- Paper I: The Shadow of the Supermassive Black Hole
- Paper II: Array and Instrumentation
- Paper III: Data processing and Calibration
- Paper IV: Imaging the Central Supermassive Black Hole
- Paper V: Physical Origin of the Asymmetric Ring
- Paper VI: The Shadow and Mass of the Central Black Hole
Press release images in higher resolution (4000x2330 pixels) can be found here in PNG (16-bit), and JPG (8-bit) format. The highest-quality image (7416x4320 pixels, TIF, 16-bit, 180 Mb) can be obtained from repositories of our partners, NSF and ESO. A summary of latest press and media resources can be found on this page.
Also at Ars Technica.
(Score: 2) by c0lo on Wednesday April 10 2019, @11:36PM (38 children)
Clearly photoshoped. I mean, look, the shadows are out of whack.
Is there any reason we are presented with a doughnut section in a black hole? Like, were we so luck that all the heat was generated on a plane that happens to be orthogonal with the observation direction? Little or no heat at all generated between the black hole and us?
(grin)
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Thursday April 11 2019, @12:06AM (21 children)
All we know is that the "donut" is much brighter than what is in the middle, not that the center is actually black.
Same as sunspots:
https://astronomy.stackexchange.com/questions/4/why-do-sunspots-appear-dark [stackexchange.com]
(Score: 3, Interesting) by c0lo on Thursday April 11 2019, @12:59AM (20 children)
It's still dubious that the doughnut has an almost perfect circle [iop.org] in the middle
M87 [wikipedia.org]
A stellar velocity map [wikipedia.org] of the galaxy suggest the M87 galaxy is rotating in a plane not exactly orthogonal on the direction we observe it.
Even more, Hubble detected a relativistic colimated jet [wikipedia.org] in M87 [wikipedia.org], suggesting the rotation axis of the M87 black hole is at an angle with the M87-Earth direction. Here's another image [wikipedia.org] generated from cm-wavelength radio emission.
If the donut shape we are observing is caused by an accretion disk, the central hole should appear elliptical.
Unless we just observed a transient phase and we were that lucky to look at the right moment (given the distance and the magnitude of the entire galaxy, what are the chances?)
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 1, Interesting) by Anonymous Coward on Thursday April 11 2019, @01:35AM
Interesting points. You should ask on stack exchange or somewhere and see what response you get.
(Score: 0) by Anonymous Coward on Thursday April 11 2019, @09:17AM (16 children)
The black hole distorts the spacetime around it (well, in some sense the black hole is the distortion), therefore what you see is not quite what you would expect from Euclidean geometry.
(Score: 2) by c0lo on Thursday April 11 2019, @09:42AM (15 children)
No matter how the spacetime is distorted near the blackhole, I find it hard to believe the circular hole in the centre.
Unless you can explain how there's little to no emission from the whole side of the event horizon facing us and intense emission on the entire circumference, your statement may hold true but it's unconvincing.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @10:38AM (14 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @10:59AM (13 children)
"E pur si muove" and "πάντα ῥεῖ"
And it just happens to spin around an axis that's oriented straight to the Solar system, for the benefit of human astronomers.
The same astronomers which observed a polar relativistic jet going on an angle and a distribution of star orbit velocities in which one side is speeding towards and the other side speeding away from Earth (heck of a misalignment between the angular momentum of the black hole gobbling those stars and the gobbled stars).
I mean... that's hell of a luck for the astronomers, don't you think?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Thursday April 11 2019, @11:49AM (1 child)
what would be really cool is if no matter (no pun intended) from where or which angle you observe and take a picture of a blackhole it ALWAYS looks like a ring O_o
(Score: 2) by c0lo on Thursday April 11 2019, @12:34PM
If you ever look down that relativistic polar jet close enough, try to use a single eye.
That way, you may keep the other eye to look later into a laser
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Interesting) by FatPhil on Thursday April 11 2019, @03:31PM (10 children)
Nope, not at all. Firstly, where did you get that "fact" from? Noone's stated it, or anything like it, so I can only imagine it's come out of some other dark hole.
One pointing towards us would be firing a high energy beam of x rays right at us. And we know it isn't as we can see that high energy beam of X rays illuminating some path off elsewhere in space, and you should know that as it was one of Hubble's most lauded photos when it was captured in high resolution.
Additionally, according to the simulations of the mathematical models, one viewed aslant would look that way too. That's why the astronomers are calling this darkness the "shadow", rather than anything else. It's an indirect effect of the actual thing there, not the thing itself. The thing itself is invisible. As is the event horizon surrounding it. And not just invisible - so perturbing of space-time that it doesn't let anything, anywhere, appear to be from the same direction as it. And because this is actual space-time being perturbed, you can even claim it is not even "behind" any more - it's "behind and to the side", as space has been bent to the side, there literally is no "behind".
It's so perturbing of space-time that it can even make some hot bright thing in front of it, and below it from the viewer's perspective, appear as if that hot bright thing is behind it and above it (simple - the light flies away from the viewer, grazes near the event horizon, and in so doing gets a gravitational slingshot back towards the viewer). That's why the mathematical model simulation images contain loads and loads of messily superimposed circular arcs - you're allowed to loop around many times before escaping - and no orbits are stable, even for light beams.
GR and black holes in particular are weird, it's fine to not understand them, but that doesn't mean it's fine to dismiss the scientists who are able to make predictive statements before experimentation and then see those statements come true to the satisfaction of many other competing scientists.
Unless you think it's all a conspiracy, and there's just a monkey with a gold spray-can locked away in some Cambridge basement. From some of the "artist's impressions" I've seen on NASA press releases, sometimes I think that might be the case...
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @09:58PM (9 children)
From the fact that the central hole looks almost perfectly circular.
Suppose that the hole would be rotating along an axis perfectly orthogonal on the observation direction. Would you still see the black perfect circle in the middle? If so, why?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @10:38PM (8 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @10:47PM (7 children)
And if the accretion disk(/rotation axis) is at an angle with the observation direction, wouldn't there be some of the accretion disks visible above the "mess in the middle"?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @11:56PM (6 children)
"the accretion disk on the "far" side that has been bent into view to that appears to be above..."
you respond:
"wouldn't there be some of the accretion disks visible above"
OK, there's a single letter typo, but really, you're taking the fucking piss now, you really are.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Friday April 12 2019, @12:35AM
Ok, mate, that's my last message on the topic.
Look at the Saturn's rings, you see them going in front of the circle that is the planet itself.
Now, go back to the black hole and, no matter from which side of the black hole (far or near) the light from the accretion disk come from, I would expect to see at least a band of light crossing that perfect circle. Yeah, Ok, maybe that band is not uniform in light intensity, but to my mind it should be something
In extreme, if the accretion disc is thick enough, I'd expect it to obscure a part of the horizon circle and transform its image into a distorted ellipse.
So far, the best explanation I got is this [soylentnews.org], positing that one won't see the accretion disc shape, but it's light after being scrambled by grav lensing and (maybe) frame drag, and that scrambled light will mostly coming from the circumference (i.e. the light coming straight from the accretion disc itself is weaker and swamped by the light that escapes the 'scrambling').
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by c0lo on Friday April 12 2019, @06:54AM (4 children)
https://www.youtube.com/watch?v=S_GVbuddri8 [youtube.com]
https://www.youtube.com/watch?v=zUyH3XhpLTo [youtube.com]
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Friday April 12 2019, @07:32AM (3 children)
The thing where I was wrong was about those oblique angles, and apparently you can see "through" where the event horizon is. My thinking was that any light path from my eye directly to the direction of event horizon would have no way of not going into the event horizon, and thus disappearing. However, the concepts of "directly to", "the direction", and "going into" stop meaning quite what you'd normally expect when space and time (this might be a time issue I've not considered) are so distorted. Even "where the event horizon is" begins to lose its meaning, as it's somewhat relative.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by FatPhil on Friday April 12 2019, @07:46AM (2 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Friday April 12 2019, @08:02AM (1 child)
It was the grav lensing that I was missing from the picture, which is first degree approx of why the accretion disc will show very weakly represented in the number of pixels on the screen and pushed away from the 'face' of the black hole.
(the bright side of our whole kerkuffle: pays to be stubbornly wrong on purpose in the search of a better answer. Sometimes, at least. Apologies for annoying you)
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Saturday April 13 2019, @08:24AM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 5, Informative) by Immerman on Thursday April 11 2019, @01:46PM (1 child)
From my understanding from one of the many articles related to these observations, with a black hole you expect to see the accretion disc "head on" no matter what direction you look at it from, due to the intense gravitational lensing it causes. We are talking about an area of space so intensely warped that light near the inner edge of the accretion disk will actually orbit around the black hole indefinitely.
In addition, we expect a uniform disc to appear very asymmetric, as it is orbiting at relativistic speeds, with half of it moving away from us (relative to the optical path), so that its emissions appear less energetic (red-shifted) from our perspective, while half moves towards us so the emissions appear more energetic (blue-shifted).
(Score: 2) by c0lo on Thursday April 11 2019, @10:16PM
Yeap, I forgot about them, thanks.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0, Interesting) by Anonymous Coward on Thursday April 11 2019, @12:15AM (15 children)
Look at ~6:50 here:
https://www.youtube.com/watch?v=P7n2rYt9wfU [youtube.com]
They generated a crapload of images from their noisy data and filtered out all the ones that didn't look like what they expected.
(Score: -1, Troll) by Anonymous Coward on Thursday April 11 2019, @01:13AM (4 children)
(Score: 2, Disagree) by c0lo on Thursday April 11 2019, @01:19AM
They may be valuable, but only by shear luck.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Touché) by Anonymous Coward on Thursday April 11 2019, @02:54AM (1 child)
Yeah, the math is more complicated than my 8th grade education, so it's obviously fake.
(Score: 0) by Anonymous Coward on Thursday April 11 2019, @04:51AM
fake = "made up by math"
(Score: 2) by FatPhil on Thursday April 11 2019, @07:47AM
Not only did they ask "if this thing is a Kerr black hole, what does it look like?", getting the answer "Kinda donut shaped, like a Kerr black hole", they also asked "if this thing is a binary pair, what does it look like?", getting the answer "Kinda donut shaped", and "if this is a spiral galaxy, what does it look like?", getting the answer "Kinda donut shaped".
It is fair to conclude that with a high probability, it's donut shaped. As predicted by the Kerr model.
I doubt there'll be a Nobel for this, but it's good science, and will only improve in time, as they expand the array (to the moon, hopefully!)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @01:17AM (9 children)
A case of begging the question [wikipedia.org]?
Fits my "That's Photoshoped" feeling.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @08:00AM (7 children)
If you saw a roadsign peppered with holes, would you say that it was invalid to pull our a bunch of simulated shotgun distributions at different guages in order to work out the likely guage and distance of firing? What if they also compared the sign to a whole bunch of photos of vomit, rhododendra, and pizzas? Do you think it's invalid for them to say "if that roadsign has a pizza on it, then it's a pizza with no bread, tomato, or cheese, so it's not a pizza"? Because that's what this team have done.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @09:52AM (6 children)
The difference between a "roadsign peppered with holes" and "the photo of the event horizon of a blackhole" is that:
- for the first you have plenty of direct observations and can organize experiments to validate your model; *while*
- for the second you don't have any other observations, not even a way to confirm your result by other means and there's no way you can organize an experiment
Crapload of what images? Of the black hole?
Threw away what? Models/algos or images?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @10:36AM (5 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @11:30AM (4 children)
And did you understand it? Enough to explain it in your own words?
---
'cause I'm hearing (09:50) "If all the image types produce a very similar looking image, we become more confident that the images we are using are not biasing the picture" - and the screen shows that all 3 types of images (including "everyday" type), after passing through the algorithm, result in the same picture of a black hole.
Which, heck of a coincidence, 2 years later, resembles the picture reconstituted from collected data.
Now, I'm not saying that "experimental data fitting" (non-linear regression by least squares, chi-square minimisation, whaevs) is invalid as a technique.
But that technique does not validate a model or and algorithm. It just says: "assuming the model is valid and the output depends so-and-so of this set of parameters, then this set of experimental data can be explained best by this set of values for parameters". However, there can be heaps of models that would explain the same experimental data.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @03:05PM (3 children)
Depending on the exact model used for the reconstruction there are very slight differences, but they all show the same general form - an asymmetric donut. The only reasonable conclusion is that they detected something that looks donutty.
A mathematical model dating back to the 60s predicts exactly such a form from a high-rotational-momentum black hole. Why do you not think this image supports that model? The reconstructions produce donuts even if you don't tell them to expect a donut. As I said elsewhere - if you ask the reconstruction to generate a binary pair, it will find you a donut.
I genuinely can't understand what it is that you can't understand, or at least why you can't understand it, sorry. Rewatch the vid.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @10:01PM (2 children)
That TeD talk youtube? Is "Published on Dec 7, 2016"
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by FatPhil on Thursday April 11 2019, @10:43PM (1 child)
Beleive it or not, they indeed did know what processing they would do with the data before capturing petabytes of it on thousands of hard disks. It's almost as if they are intelligent scientists who can do things like predict and plan and, shock horror - think!
You, however, have quite frankly started to become really tedious and annoying with ever more dumb questions that have obvious or already-supplied answers.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by c0lo on Thursday April 11 2019, @10:49PM
Ok, will leave it here, then.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by aristarchus on Thursday April 11 2019, @07:02PM
I never would have pegged c0lo as a black-hole denier. Some times one must just defer to the expertise of those who are better at confirmation bias and making stuff up than one is oneself.