Talk:Accretion disk

Hannes Alfven

The mri was actually discovered by Velikhov and Chandrashekar (see mri main article). Perhaps the work of Alfvén is related but the specific mechanism for angular momentum transport is linked directly to the mri. A precise reference to the work of Alfven should be given in any case. Repepo

Why is this picture present?

"NASA artist's misinformed concept of corona over black hole that is (wrongly) shown to hide part of the disk (as would a material body in flat space)"

Why is this picture present? Can we get one of what it rightly looks like by a correctly-informed artist? Or just remove it.178.15.151.163 (talk) 09:34, 28 January 2016 (UTC)

I wondered about that too when I first saw that, but it is not clear to me if the image is wrong, or if the caption is wrong. Orange Suede Sofa (talk) 09:39, 28 January 2016 (UTC)

Removed 'misinformed' from the caption as this seems to be a personal opinion not confirmed by the sources, if we can establish that the image is incorrect it should be removed. --184.161.106.203 (talk) 11:24, 18 February 2016 (UTC)

I'm glad the pic is here for comparison purposes, it is really common for artists to render the black hole like that but the picture is indeed incorrect (the caption is correct). Further out the accretion disk looks like that, but the part that is behind the sphere (black hole) from your point of view is warped so that you can see the entire disc that is normally hidden behind the black hole. This picture in the article is what it would actually look like up close with a small accretion disc: https://en.wikipedia.org/wiki/Accretion_disk#/media/File:CNRSblackhole.jpg If you want to know more, go here http://rantonels.github.io/starless/ or google "ray tracing a black hole" to see how light behaves around a singularity. Also http://casa.colorado.edu/~ajsh/approach.html It's really interesting! You can also see the entire surface of the singularity from any perspective at any time (with no debris in the way of course)162.219.204.36 (talk) 13:37, 13 July 2016 (UTC)

The source [27] does not state the painting is "wrongly" drawn. The examples you show are for a much smaller disk. Note that the accretion disk in the painting is much wider. What the caption should say is either the radius of the disk is wrongly depicted, or the "wrongly" statement should be removed, as it is WP:SYNTH. And we can never see the "surface" of a singularity - did you mean the event horizon?104.169.29.171 (talk) 13:47, 14 April 2019 (UTC)

I've reverted the portion of this edit which apparently added WP:OR disagreements with the supporting source cited. Wtmitchell (talk) (earlier Boracay Bill) 14:53, 14 April 2019 (UTC)

EHT image of accretion disk

It seems important to add the image recently produced by the Event Horizon Telescope to the article. The image clearly shows the shape of the M87 accretion disk and would add an important visualization to the article, which currently only shows artist conceptions. — Preceding unsigned comment added by 98.116.248.42 (talk) 16:11, 11 April 2019 (UTC)

Actually, it shows an image transformed from the non-visible radio-wave spectrum being emitted by the disk into something the human eye can relate to - it isn't a photograph of the accrection disk.104.169.29.171 (talk) 13:41, 14 April 2019 (UTC)

M87 Image

My understanding is the the M87 image is not the accretion disk, but is mroe related to effects in the photon sphere and the ergosphere inside the accretion disk. Stevelinton (talk) 09:45, 22 May 2019 (UTC)

Yes, good point. We should make sure this is clear in our use of the image here. - Parejkoj (talk) 15:41, 22 May 2019 (UTC)

Please update with: "Monitoring the Morphology of M87* in 2009–2017 with the Event Horizon Telescope"

Please add some short info on and/or images from the study to the article. It's currently featured in 2020 in science (September) like so:

Scientists publish new findings and data about the supermassive black hole M87*, including a video of the black hole based on data not sufficient for images, using statistical modeling about changes in its appearance in 2009–2017, showing variations of its orientation and a wobbling ring – constituting the "first glimpse of the dynamical structure of the accretion flow so close to the black hole's event horizon".

The study and its images are licensed under CC BY 4.0 so you could upload the images or animations to Commons and add them here as adequate.

--Prototyperspective (talk) 15:54, 22 October 2020 (UTC)

References