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Comment by djmips | Hacker News Reader

Back in 1979, Jean-Pierre Luminet created the first "image" calculated the using the IBM 7040 mainframe but drawn by hand plotting points on paper with black India ink.

The pic is cool.

https://www.engadget.com/2017/04/19/black-hole-image-jean-pi...

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> Back in 1979

The image is fantastic but one of the things that makes the story cooler, I think, is that even in 1979 the IBM 7040 was something of a relic. Although only introduced in 1963, it was superseded as early as 1964:

https://en.wikipedia.org/wiki/IBM_7040

Just goes to show that if old computer hardware is all you have access to you can still do useful and amazing things.

It looks straightforward. Skipping basically all the maths, it's equation 19 in the paper. Each contour is a line of constant z (flux), plotted in polar coords:

http://adsabs.harvard.edu/full/1979A%26A....75..228L

You plug in the viewing angle, black hole mass and some other constants which are defined in the paper (might need some fiddling to get them to look nice).

Then I think the plotter is just some monte carlo sampling and then inverted.

Off topic, but that link doesn’t work because it redirects through guce.advertising.com and I use a pi hole. I wonder if it was a deliberate decision to redirect traffic away from the site to an ad server to have it redirect back after trackers are set. Maybe they don’t care that they lost the adblock users. Still, it seems like there’s a better way than to redirect all traffic away. That makes no sense to me.

It is intentional.

Interesting. I wonder if the asymmetry in Luminet's image is due to Doppler effect (redshift on the darker right side, blueshift on the ligher left side), then why does the modern simulation not show it? Matter in the accretion disk does move at relativistic speeds after all.

I think it does show it, to me the left side is noticeably brighter than the right side.

GDPR-wall to access (part of Oath network).

Oath is really a cancer regarding GDPR. It is definitely non-compliant and makes it as worst an experience as possible to control your data.

I hope they will get the harshest fines for this.

Here is his own account of it, with more detail: https://blogs.futura-sciences.com/e-luminet/2018/03/07/45-ye...

For completeness, here is a modern simulation that also simulates the physics of accretion disk in detail: https://www.eso.org/public/videos/eso1907o/

That is really cool. Do you know if the source code is available somewhere? Would be interesting to try running it on modern hardware.

Jean-Pierre Luminet has a blog, you could ask him: https://blogs.futura-sciences.com/e-luminet/

That's awesome, thanks for the link!

This is super cool thanks for the link.

GDPR wall

EDIT: works with outline.com

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