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A comment on James Webb Telescope makes 'JuMBO' discovery of planet-like objects in Orion. Parent comment

Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by misja111 on Monday October 02, 2023 @07:45AM (#37736928)
That's a fascinating thought actually. Why does a mass of gas always have to materialize into a solar system? Why not into one or more planets, if the amount is too low? Or also the other way around: what if there is so much gas that it's too much to fit into a single star, what would it materialize into then? A twin star solar system, or something else?
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by samus on Monday October 02, 2023 @09:12AM (#37737610)
There is no "too much". The result would simply be a larger star.
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by dougmwne on Monday October 02, 2023 @09:33AM (#37737855)
There is a theorized “Eddington Limit” that stars can only grow to a certain mass before the power of their fusion reactions counterbalance gravity and they blow off additional matter instead of absorbing it. It’s approximately a few hundred solar masses.
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by liotier on Monday October 02, 2023 @11:20AM (#37739295)
How does the Eddington Limit relate to black hole formation ? Does it means that accretion is slow until the star's matter has finished fusing ?
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by samus on Wednesday October 04, 2023 @02:13AM (#37761450)
Black holes form when there is insufficient force to counter accretion and subsequent compression by gravity. There are a few forces that act as a counter:

- thermally generated pressure as a result of exothermic reactions (like nuclear fusion),

- Coulomb pressure (atomic nuclei opposing each other), or

- quantum-mechanical degeneracy pressure (keeps white and brown dwarfs and neutron stars from collapsing)

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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by andrewflnr on Monday October 02, 2023 @09:56AM (#37738186)
If you have a really big gas cloud I think you just get multiple stars, not particularly in a "solar system". There are some telescope images of stellar nurseries where you can see several young stars in the same gas cloud.
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by dotancohen on Monday October 02, 2023 @03:18PM (#37743054)
You can see the Pleiades with the naked eye.
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by ngcc_hk on Monday October 02, 2023 @06:15PM (#37745184)
Surprise so many uncertainties of the age and even distance of them https://en.wikipedia.org/wiki/Pleiades
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Re:James Webb Telescope makes 'JuMBO' discovery of planet-li... by dotancohen on Tuesday October 03, 2023 @12:05PM (#37753718)
Most of the distance measurements are within a percent of each other, except for a single survey with is 10% off all the others. That is not such a large uncertainty as to be of significant note.
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