28 ms·

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

• mkurz 7y ago
  502 Bad Gateway
  • tsukurimashou 7y ago
    Same here
  • niklasrde 7y ago
    Screenshot from press conference: https://imgur.com/UBsPgzw https://imgur.com/UBsPgzw Edit: Better posted above: https://pbs.twimg.com/media/D3y037OW0AQmpAf.jpg https://pbs.twimg.com/media/D3y037OW0AQmpAf.jpg
  • jakeogh 7y ago
    https://i.redd.it/p55wgfxsrfr21.jpg https://i.redd.it/p55wgfxsrfr21.jpg
  • acl777 7y ago
    even the black hole photo is sucking up it's own press conference! :-)
• ArtWomb 7y ago
  Breakthrough discovery in astronomy: press conference https://www.youtube.com/watch?v=Dr20f19czeE https://www.youtube.com/watch?v=Dr20f19czeE
  • ArtWomb 7y ago
    And the image itself: https://pbs.twimg.com/media/D3y037OW0AQmpAf.jpg https://pbs.twimg.com/media/D3y037OW0AQmpAf.jpg
    • piker 7y ago
      Is this image lossy compressed by Twitter? Is there an official release?
      • nathanm412 7y ago
        https://www.nsf.gov/news/special_reports/blackholes/formedia.jsp https://www.nsf.gov/news/special_reports/blackholes/formedia...
      • SiempreViernes 7y ago
        Not really, that's just the level of detail available.
• mkurz 7y ago
  Live Stream: https://www.youtube.com/watch?v=Dr20f19czeE https://www.youtube.com/watch?v=Dr20f19czeE
  • deleted 7y ago
    [deleted]
  • novaRom 7y ago
    Thanks! Over 150,000 viewers right now.
• turshija 7y ago
  Google Cache because site got stomped with traffic http://webcache.googleusercontent.com/search?q=cache:https://www.eso.org/public/ http://webcache.googleusercontent.com/search?q=cache:https:/...
  • novaRom 7y ago
    Even that page is not opening for me ...
• brink 7y ago
  Here's an article (and image) from the guardian: https://www.theguardian.com/science/2019/apr/10/black-hole-picture-captured-for-first-time-in-space-breakthrough?CMP=fb_gu&utm_medium=Social&utm_source=Facebook#Echobox=1554901867 https://www.theguardian.com/science/2019/apr/10/black-hole-p...
• mkurz 7y ago
  Here it is: https://image.futurezone.at/images/cfs_932w/3398269/bild-ist-da.jpg https://image.futurezone.at/images/cfs_932w/3398269/bild-ist...
• angrygoat 7y ago
  Here's the image via twitter: https://twitter.com/ehtelescope/status/1115964692802019328 https://twitter.com/ehtelescope/status/1115964692802019328
  • fabricexpert 7y ago
    Here's the image via a URL: https://pbs.twimg.com/media/D3yzi3dX4AEnoEp.png https://pbs.twimg.com/media/D3yzi3dX4AEnoEp.png > Scientists have obtained the first image of a black hole, using Event Horizon Telescope observations of the center of the galaxy M87. The image shows a bright ring formed as light bends in the intense gravity around a black hole that is 6.5 billion times more massive than the Sun
• e0m 7y ago
  "This is like viewing a mustard seed in Washington DC from Brussels"
  • HenryBemis 7y ago
    Pedantic/fun comment: I will assume that one of the presenters said that (I will watch the full video later tonight). One would imagine that that person knows that you cannot see a mustard seed from Brussels because the planet's crust is blocking your line of sight ;) unless the scientist who said that is a flat-earth-believer! A statement like "it is like viewing a mustard seed X kilometres/miles away would be more appropriate. And in all seriousness, I have started watching again everything-Star-Trek again (for the 5th time in my life), and news like that make me look up to the sky and think that as a species we do have a chance to move out of here and to a better future.
    • deleted 7y ago
      [deleted]
    • the8472 7y ago
      Such a photon-centric perspective. Why don't you use your neutrino perceptors to look at the seed?
• acl777 7y ago
  There are people that can't believe the Earth is round... I can't imagine what "alternative explanation" will be made to explain a black hole...
  • nukeop 7y ago
    There is still zero evidence that there exists such a thing as a black hole with all its fantastic properties. We have a picture of a red-yellow accretion disk and that's it. Black holes remain a mathematical artifact of general relativity and there is as much evidence of their existence as of crystal healing and astral travel. There is at best some evidence of very massive objects at certain points.
    • posix_me_less 7y ago
      How do you explain observed gravitational wave observed by LIGO? It is almost the same as the one calculated for coalescence of two black holes in GR.
      • nukeop 7y ago
        It's still no proof of existence of black holes. It's like saying that a lightning storm is proof of Thor, because the legends say he wields the very same lightning. The cause could be something entirely different (spontaneous spacetime ripples, alien generators, whatever really).
        • Retra 7y ago
          General Relativity is based on familiar observations, not mythical beings. It's not nearly that complex. Crystal healing and astral travel likewise don't even have a mathematical basis that is compatible with observations about reality, so there's no comparison to draw.
        • ncallaway 7y ago
          > It's still no proof of existence of black holes You've shifted the goal posts in this sentence. Previously, you said there was no evidence of black holes. Now you're upped the scale to demanding proof. The previous commenter wasn't claiming that LIGO detections were proof of black holes. They said that they were evidence of black holes. The LIGO detections, by all reasonable metrics, would certainly qualify as evidence of black holes. Of course, I agree with your assertion that taken alone, LIGO detections are not proof of the existence of black holes. Taken with the significant body of other evidence we have, though, I would say the sum total of evidence that we have is a strong indicator that black holes exist.
• niklasrde 7y ago
  The telescope's announcement is up, too: https://eventhorizontelescope.org/ https://eventhorizontelescope.org/
• turshija 7y ago
  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 https://www.youtube.com/watch?v=zUyH3XhpLTo
  • ragebol 7y ago
    Note that the prediction of the light being brighter on one side did come out.
    • jessriedel 7y ago
      What are you basing that on? (Edit:) From one of the papers released today: > The ring is brighter in the south than the north. This can be explained by a combination of motion in the source and Doppler beaming. As a simple example we consider a luminous, optically thin ring... Then the approaching side of the ring is Doppler boosted, and the receding side is Doppler dimmed...This sense of rotation is consistent with the sense of rotation in ionized gas at arcsecond scales ..Notice that the asymmetry of the ring is consistent with the asymmetry inferred from 43 GHz observations of the brightness ratio between the north and south sides of the jet and counter-jet https://iopscience.iop.org/article/10.3847/2041-8213/ab0f43 https://iopscience.iop.org/article/10.3847/2041-8213/ab0f43 (Edit 2:) Ahh, I see your comment now says "did come out". I initially read it as "did not come out", which was either a misreading on my part (likely) or an earlier edit by you.
      • typon 7y ago
        It's confirmed in the press conference by the scientists. They said its the Doppler beam effect
        • deleted 7y ago
          [deleted]
      • pcmaffey 7y ago
• itake 7y ago
  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 https://www.youtube.com/watch?v=zUyH3XhpLTo&feature=youtu.be
• crocal 7y ago
  My God, it's full of stars!
• JumpCrisscross 7y ago
  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 https://www.youtube.com/watch?v=zUyH3XhpLTo
  • jjeaff 7y ago
    So amazing that scientists were able to predict what something would look like that we have never seen before.
    • noir_lord 7y ago
      It's good science. Been able to make testable predictions and then confirming them or disproving them is the entire (awesome) point.
      • trickstra 7y ago
        ad Good science, I just randomly bumped into this video today that very nicely explains the differences between good science and bad science. https://www.youtube.com/watch?v=umo6pMCkcXs https://www.youtube.com/watch?v=umo6pMCkcXs (safely skip the first 3 minutes)
      • jjeaff 7y ago
        After having said that, I did a bit more research into how the image was made. I am of course reserving judgement as I don't fully understand the underlying technology. But it sounds like they used an interpolation algorithm to come up with the image based on renderings of what we "think" a black hole should look like. This high level overview from a ted talk goes into how they 'unbias' the data. But it is obviously on a very basic overview: https://www.youtube.com/watch?v=P7n2rYt9wfU https://www.youtube.com/watch?v=P7n2rYt9wfU
        • 7y ago
• gigatexal 7y ago
  Any word if Einstein's predictions are correct or refuted? There was word that if the shadow looked a certain way it could mean that relativity is incomplete.
  • JanSt 7y ago
    Pretty much exactly what was predicted as to the livestream :-)
  • deleted 7y ago
    [deleted]
  • misnome 7y ago
    In the discussions they said that it appeared entirely consistent with GR. Presumably more specific analysis is in papers coming afterwards.
  • hacker_9 7y ago
    General relativity predicted the event horizon, but it breaks down when trying to predict what is going on in the center, as all equations go to infinity, which is likely to be more a problem with our current understanding than what is actually happening.
    • SketchySeaBeast 7y ago
      I wonder if this is a call for another level of math. Are we just not able to take the derivative of something in respect to space time rather than just time?
  • mercwear 7y ago
    USA Today is live streaming a presentation about this from the National Science Foundation and they seem to be taking the point of view that Einstein's theory of general relativity has held up SO FAR. There is still quite a bit of research to do on the image / data which means the theory could be further proven or disproven.
• piker 7y ago
  Higher resolution official release seems to be: https://www.nsf.gov/news/special_reports/blackholes/downloads/A-Consensus.jpg https://www.nsf.gov/news/special_reports/blackholes/download...
  • hliyan 7y ago
    The additional pixel density probably doesn't add any details though. The original image looks like a smoothed-out version of a low-res image anyway...
  • hrdwdmrbl 7y ago
    Does that image have a weird pulsing optical illusion for anyone else?
    • luizfzs 7y ago
      Relieved it isn't just me
      • geoah 7y ago
        I get it if I move a bit when on an angle, I assume it's just my crappy monitor's viewing angles causing it.
    • chki 7y ago
      Yes, fascinating! If you shift the focus of your eyes from the outside to the inside of the hole, it seems to "pulsate"
    • pcmaffey 7y ago
      Yes, reminds me of the Eye of Sauron.
      • deleted 7y ago
        [deleted]
      • manaskarekar 7y ago
• zeristor 7y ago
  I wonder how it compares to the one from Interstellar? https://www.newscientist.com/article/dn26966-interstellars-true-black-hole-too-confusing/ https://www.newscientist.com/article/dn26966-interstellars-t...
  • jessriedel 7y ago
    This blog post describes the stuff Interstellar mostly gets right, and the big thing it's lacking (a brightness asymmetry from the rotation of the accretion disk). http://blogs.nature.com/aviewfromthebridge/2017/03/28/imaging-black-holes/ http://blogs.nature.com/aviewfromthebridge/2017/03/28/imagin...
    • java-man 7y ago
      If I recall this correctly, the movie intentionally simplified the rendering of the black hole (by eliminating the Doppler shift) to make it more visually appealing. Pity, really. Then again, there were other things that made no sense in the movie...
      • zeristor 7y ago
        NASA hq launching a rocket from the next door room, was my warning. Danny Boyle was confident he had “done SciFi” with Sunshine, perhaps Christopher Nolan just wanted to tick that box too. Where Kubrick led others followed; Ridley Scott was doing great to Bladerunner...
    • TheHypnotist 7y ago
      Since we're on it, there's actually a book about the science of interstellar. https://www.amazon.com/Science-Interstellar-Kip-Thorne/dp/0393351378 https://www.amazon.com/Science-Interstellar-Kip-Thorne/dp/03...
      • Insanity 7y ago
        The author (Thorne) was actually a producer for the movie, as well as a being a physics professor.
• alkonaut 7y ago
  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?
  • petschge 7y ago
    The limit in some sense is the size of the Earth. This picture is from an interferometer observing at very high radio frequencies (wavelength of 1.3 mm) using telescope around the Earth. To improve resolution you would either have to go to even higher frequencies (we have a very hard time doing interferometry there) or find baselines larger than what fits on Earth. And you don't just need a long baseline, but need to keep the baseline constant to within a fraction of the wavelength. So if you want to use satellites to get longer baselines you would have to know their orbit to within a tenth of a millimeter. As an aside: that image is basically black and white. The intensity is just mapped to black -> orange -> white instead of black -> gray -> white.
    • peatmoss 7y ago
      I wonder how important time is in collecting these data? Because if 6 months isn’t an issue, then the array size could be expanded in one axis to the diameter of Earth’s orbit around the sun, no?
      • stargazer-3 7y ago
        The collecting time is important, but mainly to 1) sample the rotation of the Earth in the Fourier space for better angular resolution and 2) for raising your overall signal-to-noise ratio is the image (but the one released is already pretty good, so not much improvement can be done there unless you're trying to go for the faint features in the image). Unfortunately, you can only do interferometry with simultaneous measurements (we need information about the difference in the phase of light hitting the receiving antennas), so the motion of Earth around the Sun is largely irrelevant, unless you can park another antenna at a trailing orbit (see space VLBI for that). What you're thinking of is probably parallax measurements of distance - that's how missions like Gaia can pinpoint distances to stars in Milky Way (and some in its satellites as well).
• patagonia 7y ago
  One difference between a Tesla or Apple style event vs a staid, scientific one such as this. Starting in the evening vs 9am...
  • legatus 7y ago
    Isn't that related to the fact that it has been announced across the world at the same time? In europe it was announced at 3 pm for example. I'm sorry, I don't understand your point
    • patagonia 7y ago
      That showmanship counts. I don’t believe HN would argue with me if I said “a strong sales group can make or break a company”. Why is it unfashionable to suggest that, in the marketplace of ideas, with an announcement of this magnitude, this exciting, this “sexy”, the presentation of the announcement would benefit from being delivered in a likewise suitable atmosphere. At night, as an event, in a cool warehouse with cool music. I’m not trying to take anything away from the inherent excitement and importance of the news. Just suggesting that the cause could be furthered even more if there was a little hype, a little showmanship. Rather than a well lit lecture hall populated by scruffy reporters, early in the morning, morning as defined in the locale the event is being held.
      • beat 7y ago
        Appropriate types and degrees of showmanship/salesmanship depend on the target customer. And scientists, by and large, don't seem to be concerned with impressing the general public - or at least, that is far secondary to the importance of impressing other scientists. One could argue that making an impression on other scientists is the basis of the scientific method. And we impress with the quality of our evidence and the repeatability of our experiments.
        • patagonia 7y ago
          > And scientists, by and large, don’t seem to be concerned with impressing the public... Some quotes from European Research Commissioner Moedas, answering the first question. “...which is that this is linking between the citizens and science, how important is that?...” “Because we want European citizens to feel connected.” “I’ve never seen this room so full.” “It’s so refreshing to come here, to see so many people, to see people clap. I mean it’s very rare in a press room to have people clapping.” During his introductory comments also, he is clearly excited and wants to engage people, and not simply through the scientific method. He talks about watching sci-fi movies as a kid and books on science. People. It’s ok to throw Science a party.
• zeristor 7y ago
  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.
  • thatcherc 7y ago
    Space VLBI is a thing already! Seems to have been around for a while [0][1]. I imagine that the challenge with during EHT-style VLBI in space is downlink bandwidth... there's just no way to get the petabytes of data they talk about down from a satellite. It's already so much data that it's easier to fly hard drives around the world than to send it over the internet, so the transfer would probably take ages over a microwave link. Maybe with laser communication in the near future but even then... it's a lot of data. Resolution-wise, the angular resolution is inversely proportional to the farthest baseline, as given by the Rayleigh criterion. [2] To get twice the resolution, you "just" need to double the size of your baseline (and do that in both dimensions, otherwise the angular resolution will be different in x & y). We've maxed out the Earth's baseline, so it seems like orbital radio telescopes are the only way to better resolution. Pretty exciting! [0] - https://www.jpl.nasa.gov/missions/space-very-long-baseline-interferometry-space-vlbi/ https://www.jpl.nasa.gov/missions/space-very-long-baseline-i... [1] - https://asd.gsfc.nasa.gov/blueshift/index.php/2016/07/25/thirty-years-of-space-vlbi/ https://asd.gsfc.nasa.gov/blueshift/index.php/2016/07/25/thi... [2] - https://en.wikipedia.org/wiki/Angular_resolution https://en.wikipedia.org/wiki/Angular_resolution
    • privong 7y ago
      > We've maxed out the Earth's baseline, so it seems like orbital radio telescopes are the only way to better resolution. Going to higher frequency gives you higher resolution for a given physical baseline length.
      • JoeAltmaier 7y ago
        For some observations, they've used the earth's moving position in space to create a synthetic-radar style image. That gives an 'aperture' of 180M miles.
• ckugblenu 7y ago
  The EU is finally learning from the US when it comes making a lot of fanfare for discoveries and other inventions.
  • Gravityloss 7y ago
    Too bad they don't present it well. I just see self congratulating politicians and officials on some youtube stream. Telling that it's a US organization that hosts the actual picture. esa.int and eso.org seem to be down actually.
    • taksintikk 7y ago
      The European broadcast presentation is not great. The speakers are referencing images and diagrams that are not visible on screen. The accomplishment speaks for itself. The delivery can be improved.
    • SiempreViernes 7y ago
      Both ESO and the NFS hosts the images, don't know what gave you any other impression. And while the EC stream was pretty bad, at least they let you skip back in the stream and left it up after the presentation ended. The NFS stream wouldn't allow you to go back (useful if you joined late) while it was up. Personally I liked the ALMA stream best, but it's down now :(
      • mlindner 7y ago
        https://eventhorizontelescope.org/ https://eventhorizontelescope.org/ is hosted in the US and the linked image links to a Harvard.edu web server.
  • chicob 7y ago
    Why is the European Commission doing this? When I recognized Carlos Moedas I immediately skipped to what mattered. The reason why he was ever appointed as Commissioner for Research, Science and Innovation is, to me, more remote than the black hole about which he knows absolutely nothing.
• deleted 7y ago
  [deleted]
• malikNF 7y ago
  The reveal happens at -27:06
• novaRom 7y ago
  Why there are two live events right now? One is from Europe, another from US: EU: https://www.youtube.com/watch?v=Dr20f19czeE https://www.youtube.com/watch?v=Dr20f19czeE US: https://www.youtube.com/watch?v=re_o0uckG-M https://www.youtube.com/watch?v=re_o0uckG-M
  • bionsystem 7y ago
    There are 6. It's an international accomplishment.
• veryworried 7y ago
  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)?
  • andygates 7y ago
    These obs are in radio. We could replace your eyes with radio eyes... ..but it's friction heating so it ought to be broadly blackbody, so I would say yes.
  • kiliantics 7y ago
    This image is a representation of radio observations. What we would see in the visible part of the spectrum would be different but the structure would likely be similar.
  • m_mueller 7y ago
    regular orbits around black holes are possible. Depending on activity if it's far enough away the radiation should be survivable, it just depends on how much matter it's eating up and whether the orbit is planar enough to its spin (otherwise its jets can be deadly).
  • azernik 7y ago
    You'd probably be dead from the radiation (that light peaks in the x-ray wavelengths) long before any of the spatial distortion effects got to you.
• montenegrohugo 7y ago
  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
  • bytematic 7y ago
    Because that collection of pixels is really out there
  • int_19h 7y ago
    I mean, in the end, everything that you're looking at is just a collection of cones and rods in your retina. It's the information that it conveys that really matters.
• huffmsa 7y ago
  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"
  • PeanutNore 7y ago
    A black hole itself (the singularity) is 1 dimensional - a single infinitesimal point. The event horizon around it is roughly a sphere. The diagrams that you are talking about are a visual metaphor that represent 3D space as a 2D plane and the 3rd dimension standing in for the influence of gravity. IRL, spacetime has 3 spatial dimensions, not 2, and gravity is not a dimension but a force. It's hard to visually represent gravitational distortion of 3 dimensional space without a 4th spatial dimension to do it with, so textbook diagrams use a 2D plane.
    • pflats 7y ago
      I think you've got a typo here: points should be 0-dimensional.
      • curlypaul924 7y ago
        Are you sure it's a typo? https://physics.stackexchange.com/a/194947 https://physics.stackexchange.com/a/194947 (I'm not a physicist.)
        • checkyoursudo 7y ago
          I believe the previous poster is referring to a typo following from this: >A black hole itself (the singularity) is 1 dimensional - a single infinitesimal point. In Euclidean geometry, A cube is 3 dimensions. A plane is 2 dimensions. A line is 1 dimension. A point is ...
        • codethief 7y ago
          Not sure why you're getting downvoted, this is a legitimate question. However, in this particular case, I think the final sentence of the accepted answer on Physics.SE, namely that > In this diagram the singularity is a line in spacetime i.e. a one dimensional object in spacetime. is wrong or at least very misleading – the answer does (correctly) say that asking for the "dimensionality of a singularity […] is a meaningless question because the spacetime geometry is undefined at a singularity".
• okket 7y ago
  The papers with the scientific details are here (open access): https://iopscience.iop.org/journal/2041-8205/page/Focus_on_EHT 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-unveiled-by-astronomers-in-landmark-discovery/ 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/askscience_ama_series_we_are_scientists_here_to/ https://www.reddit.com/r/askscience/comments/bbknik/askscien...
  • deleted 7y ago
    [deleted]
  • nonbel 7y ago
    From reddit: >"Hi, regarding the image itself: What I don't understand is why does it look like a donut and not a bright sphere? Assuming the black hole is actually spherical and not disc shaped, I would expect the Halo to be spherical and surrounding the black hole? so all we would see would be the ball of bright gas, even though there is a black hole in the middle?" This is also what I would have expected.
    • petschge 7y ago
      Things don't simply form a halo around a black hole. Instead you get a relatively flat accretion disk of things that orbit around the black hole.
    • Sharlin 7y ago
      The same reason planetary rings, solar systems, and (spiral) galaxies are flat: friction and conservation of angular momentum. Internal drag forces will eventually cancel out velocity components perpendicular to the plane of rotation, turning a cloud into a flat plane.
    • VikingCoder 7y ago
      This was a great explanation: https://www.youtube.com/watch?v=zUyH3XhpLTo https://www.youtube.com/watch?v=zUyH3XhpLTo
• modzu 7y ago
  why is it oblong???
  • delecti 7y ago
    If you mean the brightness asymmetry, it's because the accretion disc is spinning. This video predicts pretty well all of the features we expected to find, and it lines up with the actual image. https://www.youtube.com/watch?v=zUyH3XhpLTo https://www.youtube.com/watch?v=zUyH3XhpLTo
• myth_buster 7y ago
  On a tangent, interesting closing remarks from the commissioner on the importance of courage, dreams and science. Targeted towards the present anti-science climate.
• novaRom 7y ago
  Excellent example of successful international collaboration, with distributed team. Great results and promising future work: they say Sagitarius-A* is their next target!
  • deleted 7y ago
    [deleted]
• steve76 7y ago
  Will it be possible to use this data to study black hole radiation or pair production?
• _void 7y ago
  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?
  • KnightOfWords 7y ago
    Yes, we're using a telescope the size of the Earth to look at an object the size of our solar system in a galaxy about 55 million light years away. It's an infinitesimally small patch of sky. On the other hand, the jet from the M87 black hole is quite large and we have good images of it. It's even resolvable by amateurs, I hope to take a picture of it over Easter with a small telescope. https://en.wikipedia.org/wiki/Messier_87#Jet https://en.wikipedia.org/wiki/Messier_87#Jet
    • O_H_E 7y ago
      > 55 million light years didn't he correct himself and said kilometers
      • petschge 7y ago
        55 million light years is about correct. Wikipedia still has 53.5 ± 1.63 Mly from older observations, but appendix I in paper https://iopscience.iop.org/article/10.3847/2041-8213/ab1141 https://iopscience.iop.org/article/10.3847/2041-8213/ab1141 has a bit more on the distance measurements they used. They arrive at 16.76 ± 0.75 Mpc, which translates into 54.7 ± 2.4 Mly.
      • MR4D 7y ago
        He corrected himself to say 500 billion billion kilometers after mistakingly saying light years. I haven't done the math, but I believe that roughly equates to 55 million light years.
        • O_H_E 7y ago
          Yup, My bad.
  • 7y ago
• yaseer 7y ago
  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.
  • hinkley 7y ago
    If I understand it, this class of “telescope” is made up of arrays of telescopes spread as widely over the hemisphere as possible. We can only get data like this by collaborating with as many different sites as possible. It literally can’t exist without broad support from many countries. As one of the scientists said in the interview, the next step is a telescope bigger than the earth. Hopefully we can collaborate on those too but if that involves a lot of satellites in a heliocentric orbit that may limit contributions considerably.
    • aurailious 7y ago
      Constructing a telescope on Mars would be a valuable investment when a permanent presence is based there.
      • TeMPOraL 7y ago
        I hope one day we'll construct a telescope that uses the Sun for gravitational lensing. I've seen this paper once that claimed you could use it to image surface of exoplanets directly with pretty high (for our current astronomy standards) resolution. I think it talked about this: https://en.wikipedia.org/wiki/FOCAL_(spacecraft) https://en.wikipedia.org/wiki/FOCAL_(spacecraft).
      • bashinator 7y ago
        Mars is smaller than Earth, so planet-wide radio interferometry would be a smaller "aperture" than possible on Earth. If you're talking about extending the telescope to include both Earth and Mars, I imagine that doing the interferometry over changing speeds and distances would be challenging to say the least.
• zaph0d_ 7y ago
  Are there any papers already out which focus on the technical aspect of reconstructing the image? I heard that they analyzed 3.5 Petabytes of data for this.
  • petschge 7y ago
    Have a look at the papers listed at the bottom of https://iopscience.iop.org/journal/2041-8205/page/Focus_on_EHT https://iopscience.iop.org/journal/2041-8205/page/Focus_on_E... . Keep in mind that a lot of the details will NOT be in those papers as they have used CASA and AIPS, two standard software tools that have been developed over more than a decade. Details are consequently scattered over many papers. Radio interferometry is not new and there is entire textbooks on the subject. The exiting bit here is not that we go a first image from interferometry but that we have a first image of the region just around a black hole.
  • kristofferR 7y ago
    5 PB. The American unveiling focus on just what you talk about: https://www.youtube.com/watch?v=2DxjuE7WDlk https://www.youtube.com/watch?v=2DxjuE7WDlk
• ape4 7y ago
  A small thing. It could have been nice if the scientists didn't have commercial bottled water on stage. As an example to the world. Reusable personal containers would have been nice.
  • petschge 7y ago
    Most scientist I know have a reusable water bottle on their desk. And a coffee cup. But it will likely have a cat or a joke of the "astronomers do it in the dark" flavour on it. Not something you typically want to show on TV. Also they traveled from their home institutes to the location of the press conference and got handed that plastic bottle by some well-meaning PR person.
    • ape4 7y ago
      For this event they could have purchased multiple use containers for each person. Wasteful but a better image. So not really their personal containers.
• negamax 7y ago
  Does anyone remember Interstellar. Their black hole simulation was based on hard science. Looks fairly similar
  • metalliqaz 7y ago
    It doesn't look anything like Gargantua in Interstellar, but it's not really supposed to, except for the most prominent features. Interstellar showed what a black hole might look like in visible light while in orbit around it. This is a radio telescope image from a far away galaxy.
    • SiempreViernes 7y ago
      Interstellar also turned off the doppler effect, maybe to get a boring symmetric ring instead of an awesome asymmetric one as nature intended it to be!
      • CharlesColeman 7y ago
        IIRC, the black hole in Interstellar was also rapidly rotating, which I think was significant to how it looked: https://www.wired.com/2014/10/astrophysics-interstellar-black-hole/ https://www.wired.com/2014/10/astrophysics-interstellar-blac... > Nolan's story relied on time dilation: time passing at different rates for different characters. To make this scientifically plausible, Thorne told him, he'd need a massive black hole—in the movie it's called Gargantua—spinning at nearly the speed of light. > ... > Von Tunzelmann tried a tricky demo. She generated a flat, multicolored ring—a stand-in for the accretion disk—and positioned it around their spinning black hole. Something very, very weird happened. “We found that warping space around the black hole also warps the accretion disk,” Franklin says. “So rather than looking like Saturn's rings around a black sphere, the light creates this extraordinary halo.”
        • m_mueller 7y ago
          I'm still wondering why the accretion disk from the released images isn't warped in a way we saw in interstellar. Are we looking at it top-down rather than from its orbital disk? would a differently oriented black hole look more like interstellar? Veritasium also has an explanation and I don't think it has anything to do with its spin.
• Aardwolf 7y ago
  So we got an image of one in a far away galaxy before the one in the center of our own galaxy!
  • freejak 7y ago
    Is this due to occlusion?
    • petschge 7y ago
      A lot of the problems with imaging the black hole at the center of the milkway is that we would have to look along the midplane of the galaxy towards the center. That is where a lot of gas and dust is to be found and the radio waves interact with that stuff. They did take data and are working on it, but the image of M87* was easier to reconstruct and went out first.
  • kiliantics 7y ago
    Event horizon telescope has been taking data of the Sag A* black hole but the data is still being processed and yet to be released.
• r721 7y ago
  "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://iopscience.iop.org/article/10.3847/2041-8213/ab0e85 " https://twitter.com/karlglazebrook/status/1115981369711058944 https://twitter.com/karlglazebrook/status/111598136971105894...
  • SiempreViernes 7y ago
    Yeah, apparently radio interferometry is still very manual and so involves many relatively subjective decisions to produce an image. That's probably why they had several analysers that they then combined into progressively larger teams until they could produce this Consensus-A picture.
    • petschge 7y ago
      There is non-manual ways to do it (called self-calibrating), but those need many more antennas. (What you really need is good coverage of the (u,v) plane AND many more different baselines between pairs of telescopes than the number of individual antennas.) If you do not have that self-calibration fails and leads to horrible image artifact or does not converge at all. They limited the influence of the manual calibration by observing a Quasar which is basically a point source between subsequent observations of M87* to get an independent amplitude calibration.
      • SiempreViernes 7y ago
        Some quasar other than M87 I suppose :P (It is a quasar, simbad says so and that's good enough for this setting!)
        • petschge 7y ago
          Yes. They used 3C 279 which is more than 100 times further away than M87.
• csomar 7y ago
  Does this confirm or disapprove Steven Hawking Black-hole radiation?
  • symmetricsaurus 7y ago
    The Hawking radiation for a black hole with this mass would be really small. It actually decreases with added mass. So, this observation does not say anything about Hawking radiation.
    • ajuc 7y ago
      Shouldn't it increase, just with square of the radius, so it's dwarfed by all the effects that scale with cube of the radius?
      • petschge 7y ago
        The temperature is actually inversely proportional to black hole mass and the power that is radiated away even falls like the square of the mass. (A rough but illustrative derivation can be found in https://en.wikipedia.org/wiki/Hawking_radiation#A_crude_analytic_estimate https://en.wikipedia.org/wiki/Hawking_radiation#A_crude_anal... )
      • cyberfart 7y ago
        Here is an answer from SE https://physics.stackexchange.com/a/318734 https://physics.stackexchange.com/a/318734
  • GolDDranks 7y ago
    Neither. Hawking radiation - if it exists – is far too weak to be detected this way.
• sus_007 7y ago
  Here's an animated explanation of the process by the Event Horizon Telescope. https://youtu.be/hMsNd1W_lmE https://youtu.be/hMsNd1W_lmE
  • ken 7y ago
    Misspeak? This video says it's 4 million times as massive as the sun, but today's press release and Wikipedia article about it both say it's 6.5 billion times as massive.
    • ProAm 7y ago
      The black hole at the center of the milky way is 4 million times the mass of our sun, the one in the photograph is much more massive. Im guessing that is what they were referring to.
• dandigangi 7y ago
  What a time to be alive! I wish Hawking got to see it.
  • dandigangi 7y ago
    Lol, why would someone downvote this?
• harshvladha 7y ago
  Does anybody noticed that there are two brighter areas (not just one) in bottom part of the image. One at approx 8PM and one at approx 5-6PM (if seen as clock)
• colinwilyb 7y ago
  INT. EUROPEAN COMMISSION – PHONE RINGS SAMARA Seven days...
• fsakura 7y ago
  I always thought we have photographed black holes. Any idea/link to article where it explains why this took so long and why it was difficult?
  • SiempreViernes 7y ago
    Well, we have in the same sense that you take a picture of bacteria every time you take a selfie: there certainly are lots of pictures which contain black holes that are too small to be seen in them. In line with that analogy, the basic difficulty is simply that they are tremendously small compared to the sizes of galaxies.
  • etatoby 7y ago
    Because they're very small, very dark, and very distant, compared to visible objects like planets in our solar system, stars in our galaxy, and other galaxies.
  • lovehashbrowns 7y ago
    Their website talks about some of the challenges of getting a picture of a black hole: https://eventhorizontelescope.org/home https://eventhorizontelescope.org/home All of the data used to generate the image was gathered by around a dozen different telescopes around the world. The black hole itself also needs to be in a specific configuration in order for us to be able to see it. It needs to have an accretion disk that's generating light. It needs to be sufficiently large or close. And it can't be obfuscated by other astronomical objects like stars or nebulae. This black hole itself is hugeeeeee and far. It's about the size of our solar system, but it's ~52 million light years away.
  • yk 7y ago
    This is as far as I understand the first picture of a black hole shadow, that is the dark disc that indicates that there is actually light missing. Before that, there were astrophysical observations that strongly indicated that there is a black hole, for example QSOs, that is a bright combination of accretion disc and jet, that is powered by a black hole, or one paper I really liked tried to argue that there has to be a black hole in Cygni X1 because otherwise we would see the missing matter crashing into something. (Cygni X1 is a binary of a star and something very bright and the star is loosing mass.)
• stunt 7y ago
  Numbers about measures and dimensions are mind blowing. You can find articles with more details.
• ezekg 7y ago
  This is one of the most beautiful photos I've ever seen. Fascinating.
• wallace_f 7y ago
  Can someone explain in layman terms: If graviton particles or gravity waves travel at light speed, how does this information escape the event horizon?
  • AnimalMuppet 7y ago
    It doesn't. It escapes from outside the event horizon. The event horizon is the dark area in the middle.
    • wallace_f 7y ago
      A rephrasing: How does the gravity-information about what's inside the event horizon get out?
      • AnimalMuppet 7y ago
        That's a really interesting question. (And you did say "graviton particles or gravity waves" in your first post, and I missed that.) At first glance, I think that the gravity information can't escape from inside the event horizon, just like light can't. That means that the event horizon describes a frozen version of the mass inside it, not a current "live" version. And that seems to work, if you think about gravity waves. There aren't any changes to the gravitational field coming out from inside the event horizon. But it doesn't work so well if you think about gravitons. "There aren't any gravitons coming out" should be equivalent to "flat worldlines", which is very much not true just outside the event horizon. It also doesn't seem to work for a situation like a black hole merger. The spacetime outside the event horizon is this frozen snapshot, but it can still do this spiral around this other black hole? That doesn't seem to make a ton of sense. So I'm not sure my answer is very good. But it's a fascinating question. If anyone has a real answer, I'd love to hear it.
        • Pharmakon 7y ago
          It’s not that interesting unfortunately, although I liked your approach. A graviton would be just another boson like a photon, and like a photon would be unable to escape. All of the worldlines of a graviton within the event horizon would lead to a collision with th singularity. It’s just another aspect of “No Hair” on the hole. Remember that this applies everything where r≤1. As far as “flat” worldlines I think you might be thinking of a geodesic approaching r=1 in terms of a null geodesic, which isn’t necessarily true unless we’re dealing with a photon or graviton. Regions I,II of the Classic Kruskal-Szekeres extension illustrates this pretty clearly. https://en.m.wikipedia.org/wiki/Kruskal–Szekeres_coordinates#/media/File%3AKruskal_diagram_of_Schwarzschild_chart.svg https://en.m.wikipedia.org/wiki/Kruskal–Szekeres_coordinates... The total mass of the black hole (and all other information possible about it) can be described in terms of the boundary at r=1, so there’s no problem with mergers or accretion. To answer Wallace’s original question, we see no information escaping the black hole. What we’re seeing is sort of like shining a light on an absence of information, and observing the shadow cast. That’s not quite right, but it’s close.
• kristofferR 7y ago
  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 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.
  • drilldrive 7y ago
    Yeah, no kidding. The presentation in the American conference is much more insightful and gives a stronger perspective. And the EU conference didn't even show the image until 8 minutes in.
  • Karto 7y ago
    Thanks. Commissioners aren't even proper politicians : they get to power without election, without ever needing to convince the public, most often without even being known from the public. Nevertheless the decisions they make must be implemented in national laws by elected MPs. Hence you can imagine how despised and hated they are.
  • ehsankia 7y ago
    I really really liked this press conference, I highly recommend it, well worth the watch. It's fairly short (~30m for the main part) and they explain the process step by step: how it was captured -> how it was processed -> what it means. It's very well communicated in a way most can understand, it's concise and it has great accompanying graphics.
• dugluak 7y ago
  Can the equipment used from several places on earth for this be deployed in space (may be to a geostationary orbit)? Not thinking about cost for a moment is this a far-fetched thought or such a thing is technically possible.
  • Rebelgecko 7y ago
    Yeah. There were a few NASA projects attempting to do this that got cancelled circa 2010 (programs called TPF-I and SIM). Something that has been done for a while is using a single telescope in space in conjunction with some on Earth. Russia has a radio telescope in orbit called Spektr-R. I think it died recently, but Spektr-R did interferometry with other telescopes on Earth. When it was operational, I believe it was the widest VLBI array— its orbit was higher than GEO (and even intersected the moon's!), so it got pretty good distance from the ground.
• tomc1985 7y ago
  Why does the ESA always couch their discoveries in these stupid press conference panels? Every time I try to watch something of theirs it's a bunch of old people blabbing. Show the pictures and stop talking!
  • azernik 7y ago
    This isn't ESA, it's unrelated EU-funded research.
• nonbel 7y ago
  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 https://iopscience.iop.org/article/10.3847/2041-8213/ab0c57
  • LolWolf 7y ago
    As far as I know K. Bouman [0] was the scientist leading the charge on the image processing/reconstruction. A few of her later papers probably have hints [1, 2] about how this is done, but I haven't seen the official release. [0] http://people.csail.mit.edu/klbouman/ http://people.csail.mit.edu/klbouman/ [1] https://arxiv.org/pdf/1903.08832.pdf https://arxiv.org/pdf/1903.08832.pdf [2] https://arxiv.org/pdf/1702.07361.pdf https://arxiv.org/pdf/1702.07361.pdf
    • nonbel 7y ago
      Thanks, I think I added the link to the paper while you were writing this. From skimming it I can't tell the answer to my question though. How do they know what appears "black" in the image is really black vs. relatively black?
      • LolWolf 7y ago
        If you observe a very wide band of light (e.g., EM radiation) and there is nothing received from those spots, then, for all intents and purposes, the region of that image is black. Now, if you're asking if, perhaps, the region isn't really black, but rather it's emitting some sort of small radiation relative to the bright region, it would be essentially impossible to know without much higher resolving powers (since it might even be indistinguishable from the background noise generated by the surrounding region). There is no way to really know if it's "perfectly black" vs. "orders of magnitude darker than the surrounding regions."
• pontifier 7y ago
  The thought struck me that the interferometry technique used must have gathered data from a much wider field of view than of just the black hole. Burried in that 5 petabytes of data is likely a scan of a much larger field of view at a similar resolution.
  • petschge 7y ago
    Yes. But since you have a bright spot in the center of the larger image and you only have a limited number of baseline between pairs of telescopes there will be all kinds of artefacts in the outer portion of that large image. So it get's cropped away. (Most of it is actually never even computed).
    • pontifier 7y ago
      I still think it would be worth pursuing. I hope the raw data will be made available at some point... Not that I have 5 petabytes free space available right now...
• AnimalMuppet 7y ago
  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...
• hinkley 7y ago
  How jaded have I become that when I see four old men and one young person I automatically assume the younger one did all the work?
• shireboy 7y ago
  I understand this was done by coordinating multiple telescopes to create a virtual earth size scope. Why is this not done more? It seems like cloud services would make this relatively easy to share bits technically. Are the issues mostly political or are there tech issues making this harder to do more often? Tangential question: if we can do this with an earth-size virtual scope, what could we do with a larger one? Scopes on earth/moon/Lagrange points synced together.
  • ceejayoz 7y ago
    It's been done since the 1970s. https://en.wikipedia.org/wiki/Astronomical_interferometer https://en.wikipedia.org/wiki/Astronomical_interferometer There are some proposals to do it in space. https://www.universetoday.com/139566/instead-of-building-single-monster-scopes-like-james-webb-what-about-swarms-of-space-telescopes-working-together/ https://www.universetoday.com/139566/instead-of-building-sin... https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Antenna https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...
• a_d 7y ago
  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 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 https://youtu.be/oj1AfkPQa6M — first time I learnt what “warped” space-time means :)
  • pavanred 7y ago
    Sean Caroll has a great podcast, mindscape [0]. One of the recent episode featured Kip Thorne as a guest and had some great discussions about Gravitational Waves, Time Travel, and Interstellar [1]. It's a very informative and entertaining podcast, I recommend it. [0] https://www.preposterousuniverse.com/podcast/ https://www.preposterousuniverse.com/podcast/ [1] https://www.preposterousuniverse.com/podcast/2018/11/26/episode-24-kip-thorne-on-gravitational-waves-time-travel-and-interstellar/ https://www.preposterousuniverse.com/podcast/2018/11/26/epis...
    • a_d 7y ago
      Agree with the recommendation. Kip has studied black holes all his life — this podcast goes into the work on LIGO that finally got Kip (and collaborators) the Nobel Prize. I found it amusing that there is some “Nobel guilt” for scientists that comes with the prize, because the size of them teams that usually collaborate and make a large project like LIGO happen (over 20 years) is incredibly large. I also find it inspiring that Kip speaks with so much... love ... about warped space time :) There is a video that I cannot find where Christopher Nolan describes the process of rendering the black hole for his movie - they used Kip’s equations to render Gargantua and when the first images were seen, he realized that Kip has never actually seen a black hole before - even though he has spent his entire life studying it.
    • jperras 7y ago
      Wow, that brings me back. I studied GR under Robert Brandenberger, and we used Caroll's book. What a wonderful text. Definitely going to listen to his podcast!
• quadcore 7y ago
  100 billion kilometres wide, is that correct?
  • deleted 7y ago
    [deleted]
• chirau 7y ago
  MASSSIVELY UNDERWHELMING As a person who has no interest in these intergalactic shenanigans, it looks just like another ball on fire. I wanted to be excited, I really was, but this is just another picture. A giant leap for mankind, and i fully recognize that, but the awe... nada. It's just another picture really. There is nothing fascinating about it. Hats off to the people who brought this to us though. I know gravity of the matter and how daunting a task it was. Keep on!
  • jazzyjackson 7y ago
    If it fails to pique your interest, oh well, but the more you read about black holes and what is observable about them, the stranger it feels to be looking at it face to face.
  • ttul 7y ago
    Perhaps consider this: "VLBI allows the EHT to achieve an angular resolution of 20 micro-arcseconds — enough to read a newspaper in New York from a sidewalk café in Paris [6]." What's surprising about this image is how utterly microscopic the thing is that was observed - from our location. The width of the event horizon is 40 billion kilometers. That's only 267x the diameter of our orbit around the Sun. But the M87 black hole is 26,000 light years away. 26,000 light years is 2.45979e+17 km, or 639,903,746,098 times farther away than the moon.
    • phonypc 7y ago
      53 million light years. 26 thousand would still be in our own galaxy.
      • ttul 7y ago
        Quite right. Thank you for the correction.
    • chirau 7y ago
      I am fully aware of the theory and excitement over all this. I just expected something... different. I thought i'd be wowed by something new. It literally looks just like a regular photo. Is there a lot of context behind it? Sure. Is it a HUGE leap in our advancement? Definitely. Is it an eye-turning picture? NO. That is all. Black holes are fascinating, their picture simply isn't, for me at least.
• jjeaff 7y ago
  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 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?
  • RedOrGreen 7y ago
    (I haven't watched the video, but I do have professional expertise on this topic.) With interferometry, you're getting an incomplete sampling of the Fourier transform of the sky image, and if you just invert the samples, you get what we call a "dirty" image. But you know your sampling of the Fourier plane exactly, since that's just a function of the projected baselines between every pair of telescopes during the observation, so you can create a "dirty beam" - now all you have to do is remove the effects of the dirty beam from the dirty image. Of course, that's a deconvolution problem, and given that you don't have all the information - you sampled it - it can never be exact. But it can be very good! There are very sophisticated radio synthesis image deconvolution algorithms, including CLEAN and Maximum Entropy. For Maximum Entropy methods, you can apply a Bayesian prior on your images - most of the time, the prior we apply is a blank sky (seriously!) but if we have other constraints that we can use (e.g., the approximate size of the region with extended emission), Bayes tells us that we would be remiss not to use it. If you look at this image [1] from Paper IV [2], we show the image results from different techniques on different observing days. Those are the inputs to what is the "consensus image" - you can check how close they all are to each other. Does that make sense...? [1] https://iopscience-event-horizon.s3.amazonaws.com/2041-8205/875/1/L4/downloadFigure/figure/apjlab0e85f11_lr.jpg https://iopscience-event-horizon.s3.amazonaws.com/2041-8205/... [2] https://iopscience.iop.org/article/10.3847/2041-8213/ab0e85 https://iopscience.iop.org/article/10.3847/2041-8213/ab0e85
• deleted 7y ago
  [deleted]
• dangban 7y ago
  Is this a 2D slice of the actual spherical black hole? Because if a black hole is a sphere, then shouldn't the whole thing be golden?
  • scottie_m 7y ago
    The black hole is warping spacetime around it in a severe fashion. The innermost (unstable) orbit is called the photon sphere, and light can make several orbits around the hole before either falling in, or going off to infinity. The result is that (depending on the hole’s rotation relative to your point of view) you’re going to see roughly the same image we have today. You’re actually going to see multiple images of the entire hole, stretched around the outer edge, and those images multiplied and distorted again. If you could somehow “stand” by the photon spehere you’d see the back of your own head many many times. The other factor is that while the event horizon itself is a spheroid, the accretion disk of bright infalling material is not. The horizon is totally black, so it will always look roughly like seeing a disk face-on no matter where you look at it. The accretion disk is a “hoop” that’s stretched and the image is multiplied and distorted by the strong warping of spacetime in the region. As a result you get smeared and repeated views of the entire disk including portion behind the hole in a kind of bent band. Plus the whole thing is subject to strong Doppler beaming hence the bright and dark regions.
• codesternews 7y ago
  It's really amazing that human mind can predict and tell the things without even seeing it. How come we even know and predicted the radius and things far away in galaxy without even seeing it. It's just amazing. Wow it just amazes you that scientist even have predicted the radius of thing and how it work etc.[1] [1] https://www.youtube.com/watch?v=zUyH3XhpLTo https://www.youtube.com/watch?v=zUyH3XhpLTo
• laythea 7y ago
  Is this as real as the computer edited NASA images (eg of earth) or is the actually real?
• cronix 7y ago
  Now I'm really curious if Quantum Entanglement will work if you send one of the entangled particles into a black hole.
• symlock 7y ago
  For those wondering how the image was constructed: https://www.youtube.com/watch?v=hMsNd1W_lmE 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.
• return0 7y ago
  To be clear, they detected the black hole because it looked like the way we expect a supermassive black hole to be? Or were there other hints that led to it being discovered where it was?
• dugluak 7y ago
  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?
  • t3hz0r 7y ago
    As I understand it, by being more massive this black hole has roughly the same angular size in the sky as Sag A* at the center of our galaxy, but none of the dusty foreground in the way so we get a clearer vantage point.
  • bbrks 7y ago
    They did. M87* was the widely publicised "first" photo, but they also got images of Sagittarius A* (the supermassive black hole at the center of our galaxy). The difficulties with Sgr A* are twofold: - The black hole moves too much during an observation (because it's much closer, and parallax is a thing) - Sgr A* is much smaller than M87* by mass, so even though it's much closer, the angular diameter is almost the same, and the accretion disk is dimmer.
• omarchowdhury 7y ago
  The Eye was rimmed with fire, but was itself glazed, yellow as a cat’s, watchful and intent, and the black slit of its pupil opened on a pit, a window into nothing.
• jahrule 7y ago
  black ties and revelations...
• briarpatch 7y ago
  Here's today's xkcd comparing it to the size of our solar system: https://xkcd.com/2135/ https://xkcd.com/2135/
• jhallenworld 7y ago
  So how can we make a planet sized synthetic aperture optical telescope? I'm wondering if there is a way to do it with holograms (since they preserve phase information): take holograms of the object from opposite sides of the earth and then combine them offline. There are some papers in this direction: https://hal.archives-ouvertes.fr/hal-00654840/document https://hal.archives-ouvertes.fr/hal-00654840/document (spy satellites probably already do it...)
• novaRom 7y ago
  Can we see nearest stars and planets using this method? Or is it only for radio sources? One day we may even connect millions of smartphones to observe various interesting space phenomena.
• zframroze 7y ago
  This is so phenomenal. What an amazing and tremendous effort from that team!
• it 7y ago
  If you want to jump directly to the image, here it is: https://www.youtube.com/watch?v=Dr20f19czeE&t=8m28s https://www.youtube.com/watch?v=Dr20f19czeE&t=8m28s
• vertline3 7y ago
  So how come it's a ring of plasma that forms and not a sphere? Like we can see the hole unobstructed? Is it because gravity tends to clump things together? I guess Saturn's rings are the same?
  • kerbalspacepro 7y ago
    Conservation of Angular momentum collapses shapely sort of things into a disk
  • petschge 7y ago
    Saturns ring, the flattening of the accretion disk, the fact that planet systems will have most planets more or less in one plane and that spiral galaxies are flat (much thinner than they are wide at least) all have the same reason, yes. Basically most orbits align due to initial orbital momentum and the stuff that orbits in other directions sooner or later experiences enough friction to be forced into the common orbital plane.
• mythz 7y ago
  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_hole_look_like https://www.ted.com/talks/katie_bouman_what_does_a_black_hol...
• zyngaro 7y ago
  This is fantastic. But why did it take so long to prove the existence of blackholes ? are there any scientific breakthroughs that made it possible or it's more a technological achievement ?
• skanderbm 7y ago
  Reminds me of this project (building a realistic blackhole raytracer) http://rantonels.github.io/starless http://rantonels.github.io/starless
• docker_up 7y ago
  If there's a God, He must be so incredibly proud of us. What we have accomplished as a species is just mind-blowing.
• m3kw9 7y ago
  How come it so happens we are looking at the black part while the sides are bright? Does it look like a O from any angle of the sphere?
• steve76 7y ago
  I remember reading about measuring stars with something other than light. What would that look like? Knowing all particles between us and your target, and then popping a mass into existence in such a way you get a measurement?
• zakki 7y ago
  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?
  • kvartz 7y ago
    I think the 'glow' around the black hole you are thinking about is a light that was bent by gravity but hasn't gotten to event horizon.
  • usaphp 7y ago
    It almost looks like a sun eclipse.
  • tempestn 7y ago
    The black hole itself is spherical, but the light we're seeing around it isn't projected by the event horizon; rather, it's light from behind/around the black hole that isn't blocked. This video explains in much more detail: https://www.youtube.com/watch?v=zUyH3XhpLTo https://www.youtube.com/watch?v=zUyH3XhpLTo
    • usaphp 7y ago
      But if it's spherical, should not the light be all around it?
      • tempestn 7y ago
        If it were emitting the light, yes, but it's not. It's more complicated than this, but imagine holding a black sphere in front of a light bulb. You'll see a ring of light around the sphere. Somewhat separately, there's the accretion disk, which again is a disk not a sphere, much like other orbiting systems like solar systems or galaxies−the gravity between bodies orbiting the same central gravity source causes them to arrange roughly into a plane, rather than all having their own unrelated orbits. We're not seeing the accretion disk directly though, but rather the light from it, and from other sources, that is able to pass around the black hole. (ie the black sphere in front of the light bulb.) Watch that video; it explains it in a very approachable way.
• n00bdude 7y ago
  What do you reckon is in the black hole?
• sbhn 7y ago
  Why are they all wearing suits?
• samzevo 7y ago
  https://coincircle.com/l/sfX5us6vcQ https://coincircle.com/l/sfX5us6vcQ
• comiskey1905 7y ago
  thanks, i didn't watch it.
• hashfunktion 7y ago
  Pardon my naïveté, I never took advance physics, but if light can't escape from a blackhole, then how can we "take a picture" of one?
  • ceejayoz 7y ago
    Same way we can take a picture of a shadow - by taking a picture of the stuff surrounding it. This black hole is surrounded by a bright accretion disk.
  • ValleyOfTheMtns 7y ago
    It's a photo of the absence of light (in the middle) and light/particles swirling around the black hole that haven't passed the event horizon (yet).
• stewartjarod 7y ago
  At what time do they show the black hole? i hate links to videos that aren't at the time that the title is about...
• sigmaprimus 7y ago
  Anyone else getting sick of the media calling this the first "PHOTOGRAPH" of a black hole? It's a spectrograph at best and more realistically a rendering. Don't get me wrong it's really cool but it's not a photo.
  • qlk1123 7y ago
    You are wrong, this is definitely a photo, shot by multiple telescopes global-wise.
    • sigmaprimus 7y ago
      Multiple radio telescopes right? Then the data was compiled and rendered into an image, you really think it's that bright? How about orange? I wonder why it's not symmetrical? I suppose you can take multiple images combine them into one, run it through a bunch of filters and call it a photo but I still think it's more of a rendering than a photo.
      • brandonjm 7y ago
        > Then the data was compiled and rendered into an image A digital camera is just an array of tiny sensors that detect how much light hit them and a computer takes those values and renders an image from them. > you really think it's that bright? If you take a photo in a dark room with increased exposure then the resulting image is brighter than what you see with your own eyes. This was taken over a long period of time, effectively a long exposure. If you were close enough to see it at the scale you are seeing it on your computer screen it would probably be far brighter. > How about orange? As mentioned in another comment on this thread, it's just the colour scheme used in the output to show the brightness differences. The accretion disk is not necessarily orange, this photo is essentially greyscale mapped to a black -> orange -> white scale. This is just an array of relatively large sensors with very high exposure gathering information from something very far away and combining that data in greyscale. > I wonder why it's not symmetrical? See Veritasium's video [1] on why it looks like it does, in short, the effects of the black hole and our angle to the accretion disk. [1] https://www.youtube.com/watch?v=zUyH3XhpLTo https://www.youtube.com/watch?v=zUyH3XhpLTo
• OnlyRepliesToBS 7y ago
  more masturbation to the fanfare than the actual research picture
• amy12xx 7y ago
  Katie Bouman's 2017 TED video explaining how the image was taken https://www.youtube.com/watch?v=BIvezCVcsYs https://www.youtube.com/watch?v=BIvezCVcsYs
• jschrf 7y ago
  Let's say I were to jump into this black hole for fun. What happens to me? What are the chances I go somewhere cool, like another universe, versus getting turned into a spaghetti noodle?
  • doctorstupid 7y ago
    Don't it's no fun you'll get space sickness trust me.
• basicplus2 7y ago
  I have a real problem with this.. they have not taken a picture of a black hole because that is not possible.. they have at best constructed an image of some effects of a black hole. This is where top scientists do damage to science for ordinary people when they make fundamental errors in public statements.
• pulse7 7y ago
  The image of the black hole is not sharp. Isn't it possible, that the optics at that distance may make "optical mistakes" and this is not a black hole after all but maybe just some circular lightning or some darker, but not black object before some star - like in solar eclipse?