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.
Unveiling the first-ever image of a black hole [video]
261–270 of 525 posts
Re: Unveiling the first-ever image of a black hole [video]
#262Good 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
> Good video that correctly predicted the image and describes why it looks the way it does
This is of course a bummer, since this means that the acquired image does not give us any new clues of where our understanding of physics is wrong.
Re: Unveiling the first-ever image of a black hole [video]
#263It 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/…
Summary of their summary:
“arising from the rapid atmospheric phase fluctuations, wide recording bandwidth, and highly heterogeneous array”
(Filtering out bad data)
Re: Unveiling the first-ever image of a black hole [video]
#264Earlier quoted context omitted.
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 repres…
The singularity is likely a mathematical artifact of the fact that GR is insufficient to describe black holes. In reality (quantum gravity) they probably do not exist.
I would not be so sure. Its presence might simply indicate, that black hole's inner volume is infinite.
Re: Unveiling the first-ever image of a black hole [video]
#265International 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.
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.
Re: Unveiling the first-ever image of a black hole [video]
#266Previous work on this was done for the movie Interstellar. The resolution of the rendering software was so high that team members were able to examine the black hole very closely - Because Gargantua was spinning at almost the speed of light, the rendering showed that spacetime warped into shapes never seen before. This led to the publication of —> https://arxiv.org/abs/1502.03808
Kip Thorne describes his work not this in a book called the science of interstellar.
Kip’s description of black holes here is also fascinating: https://youtu.be/oj1AfkPQa6M — first time I learnt what “warped” space-time means :)
Re: Unveiling the first-ever image of a black hole [video]
#267It 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/…
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/ [1] https://arxiv.org/pdf/1903.08832.pdf [2] https://arxiv.org/pdf/1702.07361.pdf
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?
Re: Unveiling the first-ever image of a black hole [video]
#268100 billion kilometres wide, is that correct?
Re: Unveiling the first-ever image of a black hole [video]
#269MASSSIVELY 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!
Re: Unveiling the first-ever image of a black hole [video]
#270Good 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
> Good video that correctly predicted the image and describes why it looks the way it does This is of course a bummer, since this means that the acquired image does not give us any new clues of where our understanding of physics is wrong.
I expect that at the resolution that this picture is taken it would be surprising if new radically physics was found, since it would require our current models to be very different from reality to see significantly different results