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James Webb Telescope



The following was posted in another thread, but it's more relevant to this thread and to Puppycow's link:
https://arxiv.org/abs/2301.11413

A massive quiescent galaxy at redshift 4.658


The ellipses and gray text are my edits. The bold face is as in the original abstract.
Carnall et al. said:
Abstract

We report the spectroscopic confirmation of a massive quiescent galaxy, GS-9209 at a new redshift record of z = 4.658, just 1.25 Gyr after the Big Bang, using new deep continuum observations from JWST NIRSpec. From our full-spectral-fitting analysis, we find that this galaxy formed its stellar population over a ≃ 200 Myr period, approximately 600 − 800 Myr after the Big Bang (zform = 7.3 ± 0.2), before quenching at zquench = 6.7 ± 0.3. GS-9209 demonstrates unambiguously that massive galaxy formation was already well underway within the first billion years of cosmic history, with this object having reached a stellar mass of [greater than 10 billion suns] by z = 7. This galaxy also clearly demonstrates that the earliest onset of galaxy quenching was no later than ≃ 800 Myr after the Big Bang....it hosts an active galactic nucleus (AGN), for which we measure a black-hole mass of [400 to 630 million suns]....This intriguing object offers perhaps our deepest insight yet into massive galaxy formation and quenching during the first billion years of cosmic history.
 


The latest results from JWST. (If you want to skip 5:30 onwards)

There's a deep field image containing 50,000 galaxies apparently. If you have the bandwidth, it's like close to 200 MB for the full size image. The angular area is only about 1/5th the size of a full moon.

Relevent paper

Image here (you can select whether to download the full size image or something smaller).
 


The latest results from JWST. (If you want to skip 5:30 onwards)

There's a deep field image containing 50,000 galaxies apparently. If you have the bandwidth, it's like close to 200 MB for the full size image. The angular area is only about 1/5th the size of a full moon.

Relevent paper

Image here (you can select whether to download the full size image or something smaller).

Thanks for the link to the 50,000 galaxies. Could not find it elsewhere.
 
The JWST has now been operating for a year.

https://www.theguardian.com/science/2023/jul/15/scientists-james-webb-space-telescope-birth-stars

Among the objects caught in the telescope’s giant mirror is one that turns out to be the oldest known galaxy in the universe. The prosaically named JADES-GS-z13-0 appears as it did a mere 320m years after the big bang, long before the creation of our own planet. It also turns out to be tiny compared with our own galaxy, yet it was clearly creating new stars at a rate comparable to the Milky Way.

Intriguingly, this stellar fecundity is shared by several other ancient galaxies photographed by the James Webb telescope (JWST). These snapshots of the infant universe show that the first stars and galaxies had already formed and were evolving much earlier than most scientists had expected.

“These galaxies are very, very young yet they have already become hotbeds for star formation. It’s remarkable,” said Prof Brant Robertson, an astrophysicist at the University of California, Santa Cruz.

This enthusiasm was shared by Kevin Hainline, an astronomer at the University of Arizona, Tucson. “We have observed the earliest galaxies in the universe and it has been thrilling,” he told the Observer. “It has opened an entirely new chapter in the history of astronomy. It is telling us the universe was dynamic from the beginning.”
 

Cosmic timeline...

GSz13.png




 
Exoplanet may be ocean world

This is potentially very interesting:

Exoplanet's surface may be covered in oceans, James Webb Space Telescope finds

In addition to turning up carbon molecules, the JWST findings also showed the possible presence of something potentially more exciting in the atmosphere of K2–18 b.

The space telescope seems to have detected dimethyl sulfide (DMS), which on Earth is only produced as a by-product of life, mainly created by phytoplankton. The team is cautious about this detection, which is far less certain than the presence of carbon molecules. "Upcoming Webb observations should be able to confirm if DMS is indeed present in the atmosphere of K2–18 b at significant levels," explained Madhusudhan.

It's bigger than earth. About 2 to 3 times the radius and 8.6 times the mass of earth. Depending on whether the radius is closer to 2 or to 3 times the earth's, that could be anywhere from about the same as earth gravity to about twice earth gravity. For ocean-dwelling creatures with approximately neutral buoyancy that wouldn't really matter, but it would matter if there is any land or if you want to launch a spaceship from the surface. So far I don't think we've really found strong evidence for an ocean world until now. But if it is an ocean world, and there really is dimethyl sulfide, there's a pretty good case that life probably exists there. Probably not a technological civilization though, but at least something like algae and/or phytoplankton.
 
I don't know. Something about this claim just smells off. :eye-poppi

True. It is not a pleasant smelling molecule, unless you are a carrion-feeder.

Dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide have been found among the volatiles given off by the fly-attracting plant known as dead-horse arum (Helicodiceros muscivorus). Those compounds are components of an odor like rotting meat, which attracts various pollinators that feed on carrion, such as many species of flies.[17]
 


Webb snaps supersonic outflow of young star

[IMGW=800]https://cdn.esawebb.org/archives/images/screen/weic2322a.jpg[/IMGW]

Featured in this image from the NASA/ESA/CSA James Webb Space Telescope is Herbig-Haro 211 (HH 211), a bipolar jet travelling through interstellar space at supersonic speeds. At roughly 1,000 light-years away from Earth in the constellation Perseus, the object is one of the youngest and nearest protostellar outflows, making it an ideal target for Webb.
 
JWST has made the "Crisis in Cosmology" WORSE (AGAIN). YouTube by Dr. Becky.
https://youtu.be/s2gFkKDMdXg?si=Xzruc1v76U_Rp_NG&t=1220

For those that do not know there are two ways of estimating the age of the universe. And they give different results. Their margins of error do not overlap. Not even close.

When you look at the slope of the graph that results from the JWST data, it absolutely aligns with the slope of Hubble graph except that the uncertainties are much smaller.
JWST_Hubble_Tension.jpg

HST Data are the grey dots
JWST Data are the red dots


We now have two sets of data from two separate telescopes looking in different parts iof the spectrum. While they are not in perfect agreement, they nonetheless agree much more closely with each other that they do with the CMB measurements.

I think they have to be edging toward the idea that our model of the universe is wrong. There is something else going on that we are not able to observe, and therefore not able to measure.

NOTE: Maybe they ought to rename this discrepancy the Hubble-Webb tension!
 
...

I think they have to be edging toward the idea that our model of the universe is wrong. There is something else going on that we are not [YET] able to observe, and therefore not able to measure.

NOTE: Maybe they ought to rename this discrepancy the Hubble-Webb tension!
FTFY

:popcorn1

I like the name. Clearly there is "something else going on that we are not [YET] able to observe" or dark matter, dark energy and gravity would be more clearly understood.
 
The Hubble tension is about finding a value for Hubble's constant, the expansion rate of the universe.

It's not named after the telescope.

(OK, so I forgot to put a smiley after what I said... oops, my bad! :rolleyes: )

Of course, but the telescope is named after the astronomer who originally posited his "constant" almost 100 years ago. Interestingly, he suggested a figure of 500 km/s/Mpc. Today, astrophysicists argue between 68 (as suggested by the CMB, and 72 km/s/Mpc as suggested by measurement of Cepheid variables).
 
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Here's something interesting that NASA is planning to build and launch around 2036 or so:

Habitable Exoplanet Observatory (HabEx)

The Habitable Exoplanet Observatory (HabEx) is a concept for a mission to directly image planetary systems around Sun-like stars. HabEx will be sensitive to all types of planets; however its main goal is, for the first time, to directly image Earth-like exoplanets, and characterize their atmospheric content. By measuring the spectra of these planets, HabEx will search for signatures of habitability such as water, and be sensitive to gases in the atmosphere possibility indicative of biological activity, such as oxygen or ozone.



Whether they can actually manage to have it ready to launch by 2036 is another question, but it may be somewhat simpler than the JWST so maybe they can actually have it completed on or nearly on schedule.
 
Interesting article even if the title is slightly on the click-baity side:

Unprecedented discovery seems to defy fundamental astronomical theories (CNN)

Also lots of JWST images you can scroll through with the arrow buttons.

On the hunt for other low-mass isolated objects, the astronomers found something they had never seen: pairs of planet-like objects with masses between 0.6 and 13 times the mass of Jupiter that appear to defy some fundamental astronomical theories.


The scientists dubbed them Jupiter Mass Binary Objects, or JuMBOs.
 
I also enjoyed this video by Tom Scott about the VLT in Chile and the ELT that is also under construction. (Not JWST but telescope-related and I didn't want to start a new thread.)

 
Truly epic JWST image of the Orion Nebula:



If you look closely you’ll see see attack ships on fire off the shoulder.

No, but seriously this is like a poster for a movie or a book cover. It’s just beautiful. And they also found lots of cool rogue planets.
 
https://www.bbc.co.uk/news/science-environment-67243772

Imagine you could go back in time 4.6 billion years and take a picture of our Sun just as it was being born. What would it look like?

Well, you can get a clue from this glorious new image acquired by the James Webb Space Telescope (JWST).

Towards the centre of this object, called HH212, is a star coming into existence that is probably no more than 50,000 years old.

The scene would have looked much the same when our Sun was a similar age.

You can't actually see the glow from the protostar itself because it's hidden within a dense, spinning disc of gas and dust.

All you get are the pinky-red jets that it's shooting out in polar opposite directions.
 
Hey, a new space telescope's first pictures have been revealed, and they are amazing!

Euclid telescope: First images revealed from 'dark Universe' mission

Europe's Euclid telescope is ready to begin its quest to understand the greatest mysteries in the Universe.

Exquisite imagery from the space observatory shows its capabilities to be exceptional.

Over the next six years, Euclid will survey a third of the heavens to get some clues about the nature of so-called dark matter and dark energy.

It has a different mission from JWST, but seems to be quite capable of taking spectacular images of the cosmos. There's a lovely image of the Horsehead Nebula for example.
 
Here is a Youtube about JWST from SciShow. It has increased our knowledge about the universe. One small example super massive black holes that exist at the centre of galaxies formed when gas collapsed directly to form them. They did not start as stars. To find other examples watch the video.

 
Early universe ‘teeming’ with supermassive black holes (Asahi Shimbun)

Using the James Webb Space Telescope, Japanese scientists from the University of Tokyo and the National Astronomical Observatory of Japan observed, in high definition, 185 galaxies in the “distant universe,” which dates 12 billion to 13 billion years before the present time.

That’s 1 billion to 2 billion years after the universe was born, the researchers said.

They discovered 10 supermassive black holes in those galaxies, 50 times the predicted total of 0.2 for that location under existing theory.

Earlier observations had led astronomers to believe there were very few supermassive black holes during the cradle years of the universe.
 
Here's something interesting that NASA is planning to build and launch around 2036 or so:

Habitable Exoplanet Observatory (HabEx)





Whether they can actually manage to have it ready to launch by 2036 is another question, but it may be somewhat simpler than the JWST so maybe they can actually have it completed on or nearly on schedule.

Bleh. I for one am not a fan of NASA focusing its limited resources on "habitable exoplanets". Exoplanets in general, sure.

But habitable exoplanets won't be an exploitable resource in the foreseeable future. There's probably more significant cosmological observations waiting to be made. Let the people who can actually see interstellar colonization on in their future invest in finding likely candidates.
 
Bleh. I for one am not a fan of NASA focusing its limited resources on "habitable exoplanets". Exoplanets in general, sure.

But habitable exoplanets won't be an exploitable resource in the foreseeable future. There's probably more significant cosmological observations waiting to be made. Let the people who can actually see interstellar colonization on in their future invest in finding likely candidates.
NASA isn't about exploitable resources any more. The current policy is that NASA and other governmental agencies will concentrate on deep-sky exploration and research, and commercial interests will take care of exploitation. SpaceX opened that door, but they will not be the only ones to go through it.
 
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