• This forum is specifically for the discussion of factual science and technology. When the topic moves to speculation, then it needs to also move to the parent forum, Science Fiction and Fantasy (SF/F).

    If the topic of a discussion becomes political, even remotely so, then it immediately does no longer belong here. Failure to comply with these simple and reasonable guidelines will result in one of the following.
    1. the thread will be moved to the appropriate forum
    2. the thread will be closed to further posts.
    3. the thread will remain, but the posts that deviate from the topic will be relocated or deleted.
    Thank you for understanding.​

Astronomy: First ever black hole image released

Introversion

Pie aren't squared, pie are round!
Kind Benefactor
Super Member
Registered
Joined
Apr 17, 2013
Messages
10,643
Reaction score
14,867
Location
Massachusetts
Astronomers have taken the first ever image of a black hole, which is located in a distant galaxy.

BBC said:
It measures 40 billion km across - three million times the size of the Earth - and has been described by scientists as "a monster".

The black hole is 500 million trillion km away and was photographed by a network of eight telescopes across the world.

Details have been published today in Astrophysical Journal Letters.

...

The image shows an intensely bright "ring of fire", as Prof Falcke describes it, surrounding a perfectly circular dark hole. The bright halo is caused by superheated gas falling into the hole. The light is brighter than all the billions of other stars in the galaxy combined - which is why it can be seen at such distance from Earth.

The edge of the dark circle at the centre is the point at which the gas enters the black hole, which is an object that has such a large gravitational pull, not even light can escape.

The image matches what theoretical physicists and indeed, Hollywood directors, imagined black holes would look like, according to Dr Ziri Younsi, of University College London - who is part of the collaboration.

"Although they are relatively simple objects, black holes raise some of the most complex questions about the nature of space and time, and ultimately of our existence," he said.

"It is remarkable that the image we observe is so similar to that which we obtain from our theoretical calculations. So far, it looks like Einstein is correct once again."

But having the first image will enable researchers to learn more about these mysterious objects. They will be keen to look out for ways in which the black hole departs from what's expected in physics. No-one really knows how the bright ring around the hole is created. Even more intriguing is the question of what happens when an object falls into a black hole.

...
 

Tazlima

Super Member
Registered
Joined
Jun 26, 2013
Messages
3,042
Reaction score
1,494
He also recalled reading a scientific paper from 1973 that suggested that because of their enormous gravity, black holes appear 2.5 times larger than they actually are.

As someone with a layperson's passing knowledge of astrophysics, I'm trying (and failing) to wrap my brain around this part. How can the gravitational pull of an object distort perception of the object itself?

Does gravity function like color? If the same light falling on objects with different characteristics can bounce off those objects in such a way as to emphasize different colors, and emitted light can emphasize different wavelengths for the same result... does gravity do something similar, only instead of color, it affects perception of size? Does that mean we also perceive extremely small objects as smaller than they actually are?

And if we perceive a black hole as 2.5 times its actual size... how do we know it's not actually just that larger size? Or, if the massive gravity compresses matter, then maybe we perceive the matter (on, in this case, the space where the matter WOULD be if it were visible) as it would be in its normal, non-compressed state, and our perception is simultaneously accurate and inaccurate?

My brain hurts. Can someone please explain this to me?

The whole thing is just amazing.
 
Last edited:

MaeZe

Kind Benefactor
Super Member
Registered
Joined
Jun 6, 2016
Messages
12,775
Reaction score
6,483
Location
Ralph's side of the island.
This was amazing by itself:
The information gathered is too much to be sent across the internet. Instead the data was stored on hundreds of hard drives which were flown to a central processing centre.

I wonder if the roundness of a 3D donut is the actual shape or just an artifact of lighting for some other reason.

I want them to focus it. :( Surely a computer program might do the trick.
 

Auteur

Redacted
Super Member
Registered
Joined
Mar 17, 2019
Messages
553
Reaction score
42
Location
Denver
"The edge of the dark circle at the centre is the point at which the gas enters the black hole, which is an object that has such a large gravitational pull, not even light can escape."

A black hole is not an object.
 

Roxxsmom

Beastly Fido
Kind Benefactor
Super Member
Registered
Joined
Oct 24, 2011
Messages
23,083
Reaction score
10,780
Location
Where faults collide
Website
doggedlywriting.blogspot.com
"The edge of the dark circle at the centre is the point at which the gas enters the black hole, which is an object that has such a large gravitational pull, not even light can escape."

A black hole is not an object.

I think the English language lacks words to describe such a concept, though. We deal in nouns and therefore name many things that are not, strictly speaking, self-contained entities (from clouds to beams of light to shadows) as if they were discrete objects.
 
Last edited:

Xelebes

Delerium ex Ennui
Super Member
Registered
Joined
Aug 8, 2009
Messages
14,205
Reaction score
884
Location
Edmonton, Canada
I think the English language lacks words to describe such a concept, though. We deal in nouns and therefore name many things that are not, strictly speaking, self-contained entities (from clouds to beams of light to shadows) as if they were discrete objects.

John Michell's 18th century term is probably better. A "darkstar". Although a dark star might also refer to brown dwarfs who are too dim to give off any substantial visible blackbody radiation. But let brown dwarves be brown dwarves and dark stars be massive stars for which light, as little corpuscules, cannot escape Newtonian gravity.
 

Auteur

Redacted
Super Member
Registered
Joined
Mar 17, 2019
Messages
553
Reaction score
42
Location
Denver
Here's a high resolution image of the black hole:
bagel.jpg