6 ms·
Webb Telescope detects most distant active supermassive black hole
- brucethemoose2 3y agoThats a mere 0.17 AU, inside the orbit of mercury and smaller than some stars: https://www.vttoth.com/CMS/physics-notes/311-hawking-radiation-calculator https://www.vttoth.com/CMS/physics-notes/311-hawking-radiati...
- djmips 3y agoThe one in the Milky way is small as well
- ramraj07 3y agoThat’s like saying gold is less valuable than paper money because it’s small..
- brucethemoose2 3y agoThe black hole is merely ~12x as dense as gold!
- resist_futility 3y agoAre you saying the nucleus? because hydrogen is too
- OscarCunningham 3y agoFunny that by this measure, black holes get less dense as you pile stuff into them.
- kvetching 3y agoperhaps it is dying from hawking radiation considering it is so old (about 13b years)
- OscarCunningham 3y agoI 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.
- gremlinsinc 3y agohow does it know there isn't one further out past the observable universe? OR Does Webb actually see 100 percent of the entire universe?
- jperras 3y ago"Further out past the observable universe" pretty much doesn't matter (hah), by definition.
- dylan604 3y ago[flagged]
- CuriousCosmic 3y agoBy 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.
- _Microft 3y agoNo, 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 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.“
- hnthrowaway0315 3y agoIs it remotely and scientifically possible that black holes are: 1) Power sources somehow? 2) Marks of some sort of galactical weapons?
- lasc4r 3y agoThey 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 https://en.wikipedia.org/wiki/Penrose_process 2) Uh, no?
- waitforit 3y agokurzgesagt has a video about (spinning) black holes as an energy source: https://www.youtube.com/watch?v=ulCdoCfw-bY https://www.youtube.com/watch?v=ulCdoCfw-bY
- astrange 3y agoIf there was any evidence anything in the universe outside our planet had been artificially manipulated you would've heard about it.
- throwaway_ab 3y agoNot 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.
- pas 3y agoA 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 https://www.youtube.com/watch?v=EfwXWNla-Ts