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James Webb Space Telescope Finds Most Distant Known Galaxy

blogs.nasa.gov

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Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#31

Post by vlovich123 »

Pompidou wrote: post #29
vlovich123 wrote: post #11

Earlier quoted context omitted.

It's interesting that [1] has a diagram showing that in 2022 the NASA diagram claimed that stars & galaxies formed 400M years ago so this feels like a big shift to having a massive galaxy already at 300M with data suggesting it's formed after several generations of stars. > All of these observations, together, tell us that JADES-GS-z14-0 is not like the types of galaxies that have been predicted by theoretical models…

No. The diagram https://science.nasa.gov/resource/history-of-the-universe/ tells us that galaxies and dark matter formed 400M years after the big bang. Look at the right of the chart legend: "13.8 billion years" is above "today".

And this observed galaxy formed less than 300M years after the big bang. The chart is now wrong.

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#32

Post by gwerbret »

csiegert wrote: post #19
gwerbret wrote: post #13

For any astronomers here, or others with the relevant knowledge of astrophysics, a question: this discovery would suggest the existence of a fully-formed galaxy at ~290 gigayears (Gyr), when the first stars are presumed to have emerged between 200 and 300 Gyr. How badly does this damage current models of early galaxy formation, and what new physics might it suggest?

Your unit is wrong. Giga means billion. The universe is ~14 Gyr old.

You're entirely correct, my mistake; unfortunately I can't edit the comment any more.

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#33

Post by kvetching »

XzAeRosho wrote: post #4

>The presence of oxygen so early in the life of this galaxy is a surprise and suggests that multiple generations of very massive stars had already lived their lives before we observed the galaxy. For some reason this quote blew me away. It's just so hard to comprehend the timescales and vastness of the universe.

This is ridiculous. Assumes that Oxygen only is created by stars. Oxygen is one of the most abundant elements created during LENR (Low Energy Nuclear Reaction, formerly known as Cold Fusion) experiments.

https://www.nature.com/articles/s41598-023-50824-8

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#34

Post by DetroitThrow »

kvetching wrote: post #33
XzAeRosho wrote: post #4

>The presence of oxygen so early in the life of this galaxy is a surprise and suggests that multiple generations of very massive stars had already lived their lives before we observed the galaxy. For some reason this quote blew me away. It's just so hard to comprehend the timescales and vastness of the universe.

This is ridiculous. Assumes that Oxygen only is created by stars. Oxygen is one of the most abundant elements created during LENR (Low Energy Nuclear Reaction, formerly known as Cold Fusion) experiments. https://www.nature.com/articles/s41598-023-50824-8

[flagged]

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#36

Post by astro-throw »

astroH wrote: post #17
XzAeRosho wrote: post #4

>The presence of oxygen so early in the life of this galaxy is a surprise and suggests that multiple generations of very massive stars had already lived their lives before we observed the galaxy. For some reason this quote blew me away. It's just so hard to comprehend the timescales and vastness of the universe.

Multiple generations is perhaps an overstatement. The first oxygen in the Universe came from what we call Population III stars which is the first generation of stars to form after the Big Bang and what separates these from other stellar populations is that they do not have elements heavier than hydrogen or helium (except for minuscule traces left over from the Big Bang but these are insignificant). Now we don't know…

The word "generation" isn't really a thing in astronomy jargon. "Population III" is a population, and it includes stars formed after some supernovae, up to the point where the metals % gets high enough to be Population II.

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#37

Post by dredmorbius »

throwawaymaths wrote: post #22
malfist wrote: post #21

Earlier quoted context omitted.

Big stars burn hot and fast, the more mass, the shorter their lives

Pop III stars (if they existed) are really a mystery, we can't easily extrapolate. These stars would be purely hydrogen and helium so it would take them a surprisingly long time to get to CNO cycle, for example.

Why would it take a Pop III star longer than an equivalent-mass Pop I or II star to reach the end of its H / He fusion cycle?

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#38

Post by dredmorbius »

thallium205 wrote: post #35
brcmthrowaway wrote: post #26

Enough of this We need a Manhattan level project to find life. That's it.

The JWT cost more both in dollars and time than the Manhattan Project.

Not if you're looking at inflation-adjusted dollars, though the values are closer than I'd have thought.

1945 cost of the Manhattan Project, $1.89 billion,[1] or $32.9 billion 2024 per https://www.usinflationcalculator.com/>.

2016 cost of the JWST: ~$10 billion,[2] or $13.1 billion 2024 adjusted for inflation.

That's a smaller multiple for the Manhattan Project than I'd have expected, but it's still comfortably more expensive than the JWST.

________________________________

Notes:

1. https://en.wikipedia.org/wiki/Manhattan_Project#Cost>

2. https://en.wikipedia.org/wiki/James_Webb_Space_Telescope>

Re: James Webb Space Telescope Finds Most Distant Known Galaxy

#39

Post by dylan604 »

vlovich123 wrote: post #31
Pompidou wrote: post #29

Earlier quoted context omitted.

No. The diagram https://science.nasa.gov/resource/history-of-the-universe/ tells us that galaxies and dark matter formed 400M years after the big bang. Look at the right of the chart legend: "13.8 billion years" is above "today".

And this observed galaxy formed less than 300M years after the big bang. The chart is now wrong.

That's the beauty of theories in that they can be proven right or wrong. Thanks to the JWST, a lot of theories are needing to be updated. We're just now being able to actually test those theories. At some point, these types of charts will be updated.

As you stated, it is exciting times.

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