The EU is finally learning from the US when it comes making a lot of fanfare for discoveries and other inventions.
Well this was mostly a US-run effort. It's headed by Harvard University and the key South Pole Telescope is North American.
Unveiling the first-ever image of a black hole [video]
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Re: Unveiling the first-ever image of a black hole [video]
#232Earlier quoted context omitted.
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.
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 :(
https://eventhorizontelescope.org/ is hosted in the US and the linked image links to a Harvard.edu web server.
Re: Unveiling the first-ever image of a black hole [video]
#233Earlier quoted context omitted.
Does that image have a weird pulsing optical illusion for anyone else?
It's the color scheme. I think in matplotlib it's called "hot". I do a lot of 2D kernel density plots that by having a black zero level and dozens of contour levels produce a smooth look with aesthetics similarities to this. I used to use that scheme because "heatmaps" but stopped because of the pulsing illusion. I'm not sure if this image is real color or just lightness value and they used a color scheme for drama.
Grrr, why aren't scientists all using perceptually uniforms color schemes! This would still look awesome in `plasma`. Is there any where I can get the data and do it myself?
One of my favorite talks ever is on this subject: https://www.youtube.com/watch?v=xAoljeRJ3lU
Re: Unveiling the first-ever image of a black hole [video]
#234Re: Unveiling the first-ever image of a black hole [video]
#235Good 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
Wow, the video you posted is even more informative and clear than the actual press conference, and it was created by someone who hadn't even seen the image yet based purely on the mathematical predictions of what we would see.
Kind of sad that after all the amazing effort and resources that have gone into the creating the image that the international team couldn't have featured an explanation as clear as this in their actual press conference.
Re: Unveiling the first-ever image of a black hole [video]
#236Earlier quoted context omitted.
Not sure if I missed it, but can we tell which way the accretion disk is from our view of it?
perpendicular - we see it almost exactly from the top. Mentioned during the Q&A (41:33 to be exact)
If we see it almost exactly from the top, then why is one half of the ring so much brighter than the other?
Re: Unveiling the first-ever image of a black hole [video]
#237Earlier quoted context omitted.
Are north and south in astronomy defined relative to Earth’s poles? What about “lateral” directions, since east and west are relative (no poles, ie. no east of earth)?
I don't know for sure how that's defined (I ctrl-f'd and it's not explained in the paper), but this says the "North" is to the right of the image, and from context it sounds like it's the north pole of the accretion disk, i.e., the direction of the rotation axis with the right-hand rule. > The approaching side of the large-scale jet in M87 is oriented west–northwest (position angle $\mathrm{PA}\approx 288^\circ ;$ in…
In paper I, Figure 3, it says North is to the top of the image and East is to the left.
Re: Unveiling the first-ever image of a black hole [video]
#238Higher resolution official release seems to be: https://www.nsf.gov/news/special_reports/blackholes/download...
editing that image reveals all kinds of details: https://imgur.com/a/TvQsgbA (and I don't even know what I'm doing)
Re: Unveiling the first-ever image of a black hole [video]
#239Earlier quoted context omitted.
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.
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!
just for people's reference, here is the more realistic picture: https://cdn.iopscience.com/images/0264-9381/32/6/065001/Full...
i really feel they should have keep the more realistic one and dialed it up a bit. the more whispy distortions are much more awe-inspiring than the symmetrical, oversaturated version.
the source paper: https://iopscience.iop.org/article/10.1088/0264-9381/32/6/06...
Re: Unveiling the first-ever image of a black hole [video]
#240Does anyone remember Interstellar. Their black hole simulation was based on hard science. Looks fairly similar
just had my wife watch it and yea, that was the first thing I noticed, they really did a good job on the science of interstellar. When interstellar came out wired did a full magazine spread on the movie, covering its science, how they came up with the story and what the director did to make sure it was believable. idk what it looks like online but I've kept the magazine.
this presentation by kip thorne is very detailed about the science behind the movie. it's one of the best presentations i have seen, and i have watched it multiple times.