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Webb Telescope detects most distant active supermassive black hole (phys.org)
114 points by wglb 11 months ago | hide | past | favorite | 48 comments



Thats a mere 0.17 AU, inside the orbit of mercury and smaller than some stars:

https://www.vttoth.com/CMS/physics-notes/311-hawking-radiati...


The one in the Milky way is small as well


That’s like saying gold is less valuable than paper money because it’s small..


The black hole is merely ~12x as dense as gold!


Funny that by this measure, black holes get less dense as you pile stuff into them.


perhaps it is dying from hawking radiation considering it is so old (about 13b years)


I think given the current level of cosmic background radiation (3K if I remember correctly) any black holes larger than 0.1 mm (just less than the mass of the moon) will get larger over time rather than smaller.

It's only once the universe cools down to below their surface temperature that they'll start evaporating.


Are you saying the nucleus? because hydrogen is too


A very interesting video about how JWST data is already unexpected (ie. resulting in "good science", as in we already have to refine our models of the early universe and galaxy formation): https://www.youtube.com/watch?v=EfwXWNla-Ts


how does it know there isn't one further out past the observable universe? OR Does Webb actually see 100 percent of the entire universe?


No, by definition we only see the observable universe like you noted, but most people assume there is more out there beyond it. In fact, by the Copernican principle we should assume there is more out there, otherwise we happen to find ourselves exactly in the center of everything and can see exactly as far as light could have traveled in the known age of the universe.

The title is a little unclear, but I read it as the most distant known supermassive black hole. This is the farthest one we've detected, but we can assume there are further ones (even some that may still be detected by Webb in the future)


https://www.pbs.org/video/how-much-of-the-universe-can-human... is a really fascinating video to watch about the observable universe.

In some ways it’s depressing that humanity is doomed to only understanding what’s in our observable universe. I really hope we find some way around it.


Is there any reason to think what’s outside the observable universe is any different? It doesn’t depress me since we have plenty to see to get a good idea and sample size to know what exists. What does depress me is the idea that far in the future all people will see is our galaxy and not know others exist.


Yes, because what is outside of the observable universe is the light from the big bang and the time just after it


The light from big bang is inside the observable universe. It is the cosmic microwave background. We can’t see earlier because the universe was opaque before 378k years and any light from earlier stages was absorbed.


> we should assume there is more out there, otherwise we happen to find ourselves exactly in the center of everything and can see exactly as far as light could have traveled in the known age of the universe.

Is there a real argument against this view that warrants the use of "should"? Over half the world (believers in Genesis) would seem to believe we very well could be the center (with equally absent real argument).


Over half the world are not "believers in Genesis" (by which I would guess you mean biblical literalists).


Literalism has nothing to do with it. Over half the world identify as believers in Moses's God. Less than a sixth believe in Stochastic Gas. Under the Gas model, it would perhaps be strange for us to be at center. Under the God model it would not.

Regardless, to say one way "should" be the answer is a religious argument not a scientific one, and it has questionable place in a scientific discussion.


I was a bigger fan before Peter Gabriel left.


Where in Genesis does it say we are the center of anything?


It doesn't, of course. But the universe is described as being intentionally created explicitly for Earth and Man, so it wouldn't be hard to go on to think we may be at the center.

The long history of geocentricity would support this being a plausible interpretation.


Adding to the answers of others, Webb can't see the whole observable universe. It has an upper limit on wavelengths that it can detect. Because older / further away light sources are more red shifted, at some point the really old / really far away stuff drops off the spectrum range that Webb can see. Here's a nice read [0] which tells me that the oldest things Webb can see are from T = 100-250 M years after the big bang. The light from the [matter around the] black hole in the main article originated at T = 570 M years. So it is plausible to me that an even earlier one will be spotted by Webb eventually.

[0] https://jwst.nasa.gov/content/science/firstLight.html


I feel like contextually it's pretty obvious that it's simply comparing to what has been discovered thus far.


Yeah, although it's not my habit to bother with articles, I was bold enough to click this one and confirm you are correct.

First sentence: "Researchers have discovered the most distant active supermassive black hole *to date* with the James Webb Space Telescope (JWST)."


Sorry. Are you saying that you only go on hacker news and comment on articles that you haven’t read?


Yes. Your phrasing is a little different than I would use, but I think you've captured the gist. I'm not seeking out articles I haven't read to comment on, but rather I'm here for the great aspects of our community found in the comments.

I think this thread -- where a portion of the debate is about details of the headline answered by the first sentence of the article -- hints that many people are using a similar modus operandi.

My mental model is

  - comments are more entertaining
  - comments are shorter
  - comments highlight the strengths and weaknesses of the article
  - comments expand the scope of the article and point at interesting related items


I understand just reading the comments for all the reasons you mentioned, but how can you contribute to the discussion when you never took the time to understand what the discussion was about?

It’s like debating the validity of what the 10th person said in a game of telephone instead of going to the first person to understand what the origin of the idea is.

As the sibling said, that seems like a problem.


But the discussion is almost never about the article. Look around! Consider that this one isn't.

I reviewed the sibling's comment history.

  - Well that's a problem
  - If stimulus is people spending their money in the marketplace to meet their needs, I'd say it works quite well.  
  - Holding on to the best explanation until they find a better one, you mean? Yes, of course they are
  - The writer was belittling the OP so maybe direct that elsewhere
  - Nostalgia?
  - What is "woke" political stuff, specifically, vs non-woke?
  - I want to see x rays!
  - Linkding is great, and has some browser extensions to inject your favourites into relevant search pages on the likes of google, ddg, bing, etc, which was a nice idea I hadn't considered before
  - Have you tried kbin?
  - It's both hilarious and unintuitive, but for some people their personal familiarity trumps most other things
None of those are about the article! Great, engaging comments. Nice pointers to interesting tools -- Linkding, kbin. Some economics, some psychology, some tech. Not a single reference to the article, none on the same topic as the article.

:)


Good points. Especially about our discussion here. I guess I would narrow it and say as long as it’s not a commentary on the article itself then no worries! If someone is commenting on the article without reading then I still feel like I would rather them read it first so we can have the same definitions.


> If someone is commenting on the article without reading

Yeah, I hear you. I note in my case, I read the article and posted about the clarifying sentence.

I did find it funny that so many people were in an animated discussion about the interpretation of the headline.

  gremlinsinc: "how does it know there isn't one further out past the observable universe?"
  doctoboggan: "the title is a little unclear, but I read it as the most distant known supermassive black hole"
  dotnet00: "I feel like contextually it's pretty obvious "
Obviously without reading the first sentence of the article.


Well that's a problem


"Further out past the observable universe" pretty much doesn't matter (hah), by definition.


[flagged]


They still don't matter from our point of view, since everything outside the hubble sphere is by definition completely causally disconnected from us due to moving away from us faster than light.

The main value of these sorts of detections is towards probing the early ages of the universe and how quickly certain things formed, in which context, the idea of a larger black hole beyond the edge of the observable universe doesn't make much sense, since the edge of the observable universe is t=0 for the big bang (to be precise, the edge observable via photons is actually t=~370k years, the point where the universe cooled enough to be optically transparent, but theoretically we could look to t=~1 second if we could devise a way to detect relic neutrinos from the big bang).


It sort of does because it had an impact on the formation of our part of the universe in the beginning, sorry it is useful in understanding the formation of the universe


We don't know the shape of the universe. There could be nothing further than what we observe. We, by definition, cannot actually know. The universe may simply wrap around itself. The universe may have finite real volume due to big bang inflation and it simply can't be approached

Fact is, far enough in the future inflation will be such that our view is vastly smaller than it is now. Their universe will be smaller because there will be no way for them to access what inflation has put beyond light and causality.


What you’re calling narcissistic is nothing more than taking as a given that an observer can’t go faster than the speed of light.


By definition if we can observe it (either directly or indirectly via the effects on stuff we can directly observe), it's part of the observable universe.

If it's outside the observable universe then by definition it has no observable effect. Until technology improves to expand the observable universe to a degree that we can observe it or it does something that allows us to observe it (which adds it to the observable universe), then it doesn't really matter to us.

In other words: If it's not part of the observable universe, it doesn't matter to us because we can't possibly know anything about it. However as soon as we discover something about it, it becomes part of the observable universe and now we can care about it because we know of it.


No, it does not depend on our technological capabilities. The observable universe [0] of a point is defined as the space from which it is theoretically possible that a signal can reach it. So: every point in space has its own observable universe and it is not dependent on any technological capabilities.

[0] https://en.m.wikipedia.org/wiki/Observable_universe

Edit, excerpt from [0]: „The word observable in this sense does not refer to the capability of modern technology to detect light or other information from an object, or whether there is anything to be detected. It refers to the physical limit created by the speed of light itself.“


Lol, no. "Observable universe" is not a philosophical concept; it's a physical one with a precise definition: those parts of the universe that fell within our past light cone.


First sentence: “ Researchers have discovered the most distant active supermassive black hole to date with the James Webb Space Telescope (JWST).”


It doesn’t know, this is the most distant it has detected so far


Is it remotely and scientifically possible that black holes are:

1) Power sources somehow?

2) Marks of some sort of galactical weapons?


Not by themselves.

However there are theories on how a super advanced civilisation could achieve your points 1 and 2:

1) Use black holes as a power source. This works by encasing a rotating black hole in a Dyson sphere where the inside is coated in perfect mirrors. Then you fire lasers across the inside to the other side (not into the black hole). (I think you fire your laser in the direction the black hole is rotating.) This light steals some of the black holes rotational energy and just keeps on building up as it bounces off the mirrors and around the black hole. As the energy builds you then bleed off the higher energy beams - this is your power source, likely the greatest power source ever to exist.

2) See (1) above. Now instead of bleeding off the energy in a reasonable way, you just keep the entire thing 100% sealed after you fire your first beams, and just let the runaway laser beams gain in energy for a much longer time. You might need stronger mirrors? This can now be weaponised as follows:

A) Do nothing. It'll eventually gain too much energy for your containment and explode. Literally a black hole bomb. So the way this strategy works is you find a suitable black hole near your enemy and build your Dyson sphere, start your laser ignition then leave. Eventually it'll explode and obliterate anything within range. I'm not quite sure what the range would be.

B) The above are ideas I learnt from a Kurzgesagt video. My humble addition to this ridiculous concept is instead of letting the thing become a bomb, just let the energies build way past power generation scales, but before your Dyson sphere breaks down, and open a directional channel, like imagine a cylinder with the same mirrors on the inside aimed like lenses and this cylinder sticks out from the sphere on the outside. Now open a hole in the shell for light to pour out into your cylinder lens "gun barrel" and ensure its aimed at a star system you want to obliterate. Now you have something potentially more powerful than any astrophysical/relativistic jet and on demand.


I like the direction but have a feeling that 1) the mirrors would give in at some point in time. There are no perfect mirrors. 2) the energy required to stabilize this contraption would be higher than what you could extract from the bh


They are just regions of spacetime with a lot of mass and very strong gravity.

1) They aren't power sources, but if they are spinning that rotational energy could theoretically be harnessed: https://en.wikipedia.org/wiki/Penrose_process

2) Uh, no?


kurzgesagt has a video about (spinning) black holes as an energy source: https://www.youtube.com/watch?v=ulCdoCfw-bY


If there was any evidence anything in the universe outside our planet had been artificially manipulated you would've heard about it.


Yeah, whiffs joint totally dude!




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