Event Horizon Telescope Results Released Yesterday (April 10, 2019)

[mfb]

Media Advisory: Press Conference on First Result from the Event Horizon Telescope
April 10, 15:00 CEST (13:00 UTC. In 8 days and 13 hours)
Livestream links are on that website.

The Event Horizon Telescope is a collection of radio telescopes all over the world which recorded data from the supermassive black hole in the center of the Milky Way. Combining the different data sets leads to a virtual telescope as large as Earth in terms of angular resolution - good enough to resolve the area directly around the black hole.

This article shows some simulations how it might look like.Edit: The first image:

 

[berkeman]

Sorry, what are those simulations supposed to be showing? The SMBH eclipsing a star that is near the center of the MWG? Sorry if I'm missing the obvious...

 

[mfb]

The accretion disk around the black hole - gas and random other stuff orbiting the black hole closely. Brighter: More stuff.

There shouldn't be stars that close. We know one that has a periapsis speed of 3% the speed of light, but that is still outside the range the Event Horizon Telescope is interested in.

 

[m4r35n357]

Hmm, apparently it is "a groundbreaking result from the EHT".

 

[PAllen]

I guess this will expand the horizon of our knowledge...

 

[Greg Bernhardt]

EHT is targeting two black holes, the biggest in the sky from our point of view. The first is Sagittarius A*, the supermassive black hole at the centre of the Milky Way, while the second is an even larger black hole at the centre of the Messier 87 galaxy, found in the constellation Virgo.

https://www.newscientist.com/articl...re-of-a-black-hole-may-be-revealed-this-week/

 

[mishima]

Is this just a first light/data release or is there some accompanying journal article?

 

[mfb]

I'm sure there will be at least a note, but probably a preprint or publication that comes with the press conference.

 

[mfb]

This is in one hour from now!

Livestream e.g. here at ESO.

 

[mfb]

Kind of like the simulations...
Screenshot, poor quality.

Edit: After some color corrections and so on. Left observation, right a theory prediction.

 

[Orodruin]

M87 it is!

 

[Greg Bernhardt]

 

[robphy]

4000x2330 Image available from NSF
https://www.nsf.gov/news/special_reports/blackholes/formedia.jsp

 

[websterling]

The papers are are published in the current The Astrophysical Journal Letters and are available here-
https://iopscience.iop.org/journal/2041-8205

 

[tade]

View attachment 241628

I wonder what the implications for Hawking radiation and other black hole theories are.

Also, there's just too much crap in the way to get a clear shot of Sagittarius right?

 

[websterling]

I wonder what the implications for Hawking radiation and other black hole theories are.

There would be no implications for Hawking radiation. A black hole this massive would essentially have a temperature of absolute zero.

 

[Drakkith]

Amazing picture!

 

[Amrator]

So does this count as the first direct detection of black holes?

 

[aabottom]

Full size 7416x4320 tiff (182.4 MB) available here:
https://www.eso.org/public/images/eso1907a/

 

[Drakkith]

Video from Veritasium on how to understand the image of a black hole:

 

[berkeman]

Sorry for the dumb question (especially if it's already been addressed), but if they used 8 radio telescopes to form this image, where did the visible light colors come from?

https://abc7news.com/science/heres-the-first-ever-direct-image-of-a-black-hole/5241612/

 

[russ_watters]

Cool picture, but what is actually new here? Haven't we already gotten pictures of matter falling into black holes? Is this just cooler because it's circular and black in the middle?

 

[russ_watters]

Sorry for the dumb question (especially if it's already been addressed), but if they used 8 radio telescopes to form this image, where did the visible light colors come from?

Colorization. Somebody picked them.

 

[aabottom]

Video from Veritasium on how to understand the image of a black hole:

This is a very good explanation of what the black hole image shows.

 

[tade]

Colorization. Somebody picked them.

what is the visible spectrum image expected to look like? Based on the physics, I'm guessing almost identical to the radio image?

 

[Orodruin]

Haven't we already gotten pictures of matter falling into black holes?

No.

 

[mfb]

The colors just visualize the intensity of the (radio-wave) radiation. Brighter/yellow: More radiation. Darker/red: Less radiation. It is synchrotron radiation, visible light would come from thermal radiation, it can have a different distribution. Gas clouds between the black hole and us absorb too much visible light.

@russ_watters: It is the first time we see a black hole as more than just a point-like object in the sky.

 

[russ_watters]

No.

I'm really not trying to be difficult, but how is this new image any different from that standpoint, from this one:

@russ_watters: It is the first time we see a black hole as more than just a point-like object in the sky.

So, high enough resolution that we can see a black disk in the middle? Fair enough.

 

[Orodruin]

I'm really not trying to be difficult, but how is this new image any different from that standpoint, from this one:

You are not really seeing the event horizon. You are seeing the products in terms of radiation coming from there but it is a point object so you have not really resolved anything. This image resolves the direct effects near the event horizon.

 

[jedishrfu]

Sorry for the dumb question (especially if it's already been addressed), but if they used 8 radio telescopes to form this image, where did the visible light colors come from?

https://abc7news.com/science/heres-the-first-ever-direct-image-of-a-black-hole/5241612/
View attachment 241632

View attachment 241633

They used a paint-by-numbers kit.

Also the picture kind of looks like a smiley face maybe it knows it'll gobble up our planet sometime in the distant future perhaps and end of simulation for us.

 

[Orodruin]

I had a colleague put a rewriting of the Ring Verse from Lord of the Rings so I had to counter with a limerick:

There once was a black hole named Kevan,
so big and far up in heaven,
in the accretion disk
you'll know you're at risk
to be eaten by M87

Edit: He re-countered so I had to write another one ...

In a galaxy far far away
A long time ago, so they say
An enormous black hole
went out of control
its ring was the unwilling prey

 

[pinball1970]

First story on radio 1 and 2 all day beating Brexit and Israeli elections

 

[virgil1612]

Does the light come from the accretion disk?

 

[davenn]

Does the light come from the accretion disk?

Yes, the generated image of the radio signals that you see are coming from the accretion disk

ohhh and it isn't "light" it isn't optically visible ( that is ... this IS NOT an optical image)...
the radio emissions are at very short microwave radio wavelength, 1.3mm ( frequency ~ 230 GHz)Dave

 

[davenn]

but if they used 8 radio telescopes to form this image, where did the visible light colors come from?

Colorization. Somebody picked them.

yes ... so the brighter the colour, the stronger the radio emissionoops, I see @mfb commented the same