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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]

#131

Post by KnightOfWords »

_void wrote: post #114

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?

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

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

#132

Post by petschge »

zaph0d_ wrote: post #117

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.

Have a look at the papers listed at the bottom of 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.

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

#133

Post by [deleted] »

HenryBemis wrote: post #115
e0m wrote: post #14

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

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…

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

#134

Post by stargazer-3 »

zeristor wrote: post #45

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.

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

One of the reasons they've imaged M87* rather than a black hole in our own galaxy was to avoid dealing with ISM scattering - we don't have to look through our edge-on disk, so it's easier to image another galaxy's center somehow. But the Sgr A* image might be in the works already, it was mentioned in both the press-conference and one of the paper's future work section.

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

#135

Post by metalliqaz »

negamax wrote: post #125

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

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.

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

#136

Post by curlypaul924 »

pflats wrote: post #103
PeanutNore wrote: post #82

Earlier 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…

I think you've got a typo here: points should be 0-dimensional.

Are you sure it's a typo?

https://physics.stackexchange.com/a/194947

(I'm not a physicist.)

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

#138

Post by bparsons »

hrdwdmrbl wrote: post #32
piker wrote: post #30

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

Does that image have a weird pulsing optical illusion for anyone else?

I think my eye is trying to bring it into focus. It is like when the camera on your phone can't quite figure out what it is looking it and keeps adjusting.

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

#139

Post by [deleted] »

oppositelock wrote: post #98
huffmsa wrote: post #70

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"

1. Yes, but it's also up for debate, since it's also known that the information content of a black hole is proportional to its surface area, so 2D. 2. The event horizon is spherical. Mathematically we treat it as a point. Nobody knows. 3. It's a gravity well, so everything falls towards it like it does towards the earth. Since it's the center of a galaxy, and galaxies form a 2D spin plane, most matter will be circlin…

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