Jump to content

The James Webb Space Telescope and stuff


Streetwind

Recommended Posts

Back when Hubble (the astronomer) was doing his work, negatives were the norm. 

http://ircamera.as.arizona.edu/NatSci102/NatSci102/images/m33hub.jpg

Here is one of Hubble's photographic plates of the center of M33, with Cepheid variables marked. If you look closely (and if the original resolution has been preserved from plate to journal to scanner to web page to your computer), you will see that the gray "nebulosity" is broken up into little specks that are individual stars. (The plate is a negative, as was the convention for publishing results -- the stars look black and the sky white) (From ApJ, 63, 236, 1926)

 

 

Link to comment
Share on other sites

On 12/27/2022 at 3:44 AM, JoeSchmuckatelli said:

The James Webb Space Telescope resumed science operations Dec. 20, after Webb’s instruments intermittently went into safe mode beginning Dec. 7 due to a software fault triggered in the attitude control system

-from the Blog 

I missed this information, I thought it was not published.

Link to comment
Share on other sites

STScI-01GKT0JD103CVYR7VVPMQN1JQQ.png

From these images (shown at left), the team searched for faint galaxies that are visible in the infrared but whose spectra abruptly cut off at a critical wavelength known as the Lyman break. Webb’s NIRSpec instrument then yielded a precise measurement of each galaxy’s redshift (shown at right). Four of the galaxies studied are particularly special, as they were revealed to be at an unprecedentedly early epoch. These galaxies date back to less than 400 million years after the big bang, when the universe was only 2% of its current age

https://webbtelescope.org/contents/media/images/01GKRX20YPY9XSXRWX31H57P2A

 

Oh - and if you are wondering about the Lyman Break: https://en.m.wikipedia.org/wiki/Lyman-break_galaxy

Link to comment
Share on other sites

ZBgXNTwa7citSTmURQguTV-1200-80.png.webp

 

These first observational results from an Earth-size, rocky planet open the door to many future possibilities for studying rocky planet atmospheres with Webb,

The team observed LHS 475b as it transited twice in front of its host star, a red dwarf that the planet orbits every two days. The first transit occurred on Aug. 31, 2022, and the second one happened four days later, on Sept. 4. Lustig-Yaeger's team recorded that 0.1% of the star's light was being blocked by the planet over the course of its 40-minute transits. From that, the team calculated that the planet is almost the same size as Earth, with roughly 99% of its diameter.  

 

https://www.space.com/james-webb-space-telescope-first-rocket-exoplanet

 

Edited by JoeSchmuckatelli
Link to comment
Share on other sites

JWST keeps revealing weirder and weirder stuff about the universe.

nrao23ao02b_full-1024x576.jpg

One galaxy is apparently traveling so fast relative to the others that it is generating a massive shock wave.

Quote

NGC 7318b, violently intrudes into the group at a relative speed of roughly 800 km/second. At that speed, a trip from Earth to the Moon would take just eight minutes. “As this intruder crashes into the group, it is colliding with an old gas streamer that likely was caused by a previous interaction between two of the other galaxies, and is causing a giant shockwave to form,” said Philip Appleton, an astronomer and senior scientist at Caltech’s IPAC, and lead investigator on the project. “As the shockwave passes through this clumpy streamer, it is creating a highly turbulent, or unsteady, cooling layer, and it’s in the regions affected by this violent activity that we’re seeing unexpected structures and the recycling of molecular hydrogen gas. This is important because molecular hydrogen forms the raw material that may ultimately form stars, so understanding its fate will tell us more about the evolution of Stephan’s Quintet and galaxies in general.”

ALMA and JWST Reveal Galactic Shock is Shaping Stephan’s Quintet in Mysterious Ways - National Radio Astronomy Observatory (nrao.edu)

 

Lighter fare article about the paper above:

Webb Telescope Finds Massive Shock Wave Wreaking Havoc Among 5 Galaxies (msn.com)

 

Link to comment
Share on other sites

  • 2 weeks later...
  • 5 weeks later...

230222095505-webb-massive-galaxies.jpg?c

Webb captured images of the six massive galaxies. One of them (bottom left) could contain as many stars as our Milky Way galaxy, but it is 30 times more compact

"The revelation that massive galaxy formation began extremely early in the history of the universe upends what many of us had thought was settled science,” Leja said. “We’ve been informally calling these objects ‘universe breakers’ — and they have been living up to their name so far.”

These objects are way more massive than anyone expected,” said study coauthor Joel Leja, assistant professor of astronomy and astrophysics at Penn State University, in a statement. “We expected only to find tiny, young, baby galaxies at this point in time, but we’ve discovered galaxies as mature as our own in what was previously understood to be the dawn of the universe.”

The galaxies are so massive that they conflict with 99% of models representing early galaxies in the universe, which means scientists need to rethink how galaxies formed and evolved. The current theory suggests that galaxies began as small clouds of stars and dust that grew over time

https://www.cnn.com/2023/02/22/world/webb-telescope-massive-early-galaxies-scn/index.html

 

Link to comment
Share on other sites

At the JWST Early Science Conference back in December, they teased the results for the sub-Neptune GJ 1214b. During a 38 hour long observation, JWST was able to observe the day side of the planet right before it passed behind its star and collect information on its atmospheric composition, which has been a pain to do for more than a decade due to a thick layer of clouds/hazes. The lead authors of this investigation said that they still have work to do on the data, but have found evidence for water and methane, and the data seems to show that the atmosphere is enriched in compounds heavier than hydrogen and helium. The planet's bulk density is compatible with either a H/He atmosphere over a rocky core and small water mantle or a gigantic water mantle with a steam atmosphere, and it seems to me that the preliminary JWST results are pointing towards the latter. I'm quite excited for the paper on this investigation. GJ 1214b was one of those early exoplanets that really got me excited about and into the field.

Also GJ 1214b is one of twenty exoplanets targeted by JWST to be in the IAU's third NameExoWorlds campaign. Some of the name submissions are available on YouTube. Two Greek organizations submitted names (Laurus and Bellerophone), but only one name submission is accepted per country, so only one has made it to the ongoing final vote. Which one did is unknown. I do wish the IAU would allow multiple names per country because it didn't seem like there were a ton of good ones being submitted, and some planets may get more submissions than others. 

Link to comment
Share on other sites

  • 3 weeks later...

stsci-01gtyana7snwzaftfrdhqb8chd.png

luminous, hot star Wolf-Rayet 124 (WR 124) is prominent at the center of the James Webb Space Telescope’s composite image combining near-infrared and mid-infrared wavelengths of light from Webb’s Near-Infrared Camera and Mid-Infrared Instrument

 

https://www.nasa.gov/feature/goddard/2023/nasa-s-webb-telescope-captures-rarely-seen-prelude-to-supernova

 

Link to comment
Share on other sites

  • 3 weeks later...

Just a heads-u, for most of its life under our observation, Uranus did not have visibly distinct features, but recently its pole went brighter. It's not like in images released by Hubble and falsely advertised as normal images made in light, where it's bright white, but subdued, brighter blue than its normal sky blue color.

More JWST pictures here.

https://www.nasa.gov/feature/goddard/2023/nasa-s-webb-scores-another-ringed-world-with-new-image-of-uranus

Link to comment
Share on other sites

STScI-01GXE4ADD2VWC1BTTEQSFNSMGC.png

This image of the Hubble Ultra Deep Field was taken by the Near-Infrared Camera on NASA’s James Webb Space Telescope. The Webb image observes the field at depths comparable to Hubble – revealing galaxies of similar faintness – in just one-tenth as much observing time. It includes 1.8-micron light shown in blue, 2.1-micron light shown in green, 4.3-micron light shown in yellow, 4.6-micron light shown in orange, and 4.8-micron light shown in red (filters F182M, F210M, F430M, F460M, and F480M). 

We proposed to image the Ultra Deep Field using some of Webb’s NIRCam’s medium-band image filters, which allowed us to take images of spectral features more accurately than we could with broadband filters because medium-band filters span a shorter wavelength range. This gives us more sensitivity in measuring colors, which helps us understand the history of star formation and ionization properties of galaxies during the first billion years of the universe, like in the Reionization Era. Measuring the energy that galaxies produced in that time will help us understand how galaxies reionized the universe, reverting it from being neutral gas to once again being an ionized plasma like it was after the big bang.

James Webb Space Telescope (nasa.gov)

 

Link to comment
Share on other sites

  • 3 weeks later...

Totally unknown to me - but apparently stars contain water vapor.  If asked I'd have guessed that to be impossible - and been boldly wrong. 

Webb detects water vapor while staring at a tidally locked super-earth transiting its host Red Dwarf. 

The question is whether the water vapor signal is evidence of an atmosphere surrounding the tidally locked planet, or a background signal from the star itself 

https://www.nasa.gov/feature/goddard/2023/webb-finds-water-vapor-but-from-a-rocky-planet-or-its-star

Link to comment
Share on other sites

I’d guess most likely the planet, but an older generation star might have a mix of oxygen and hydrogen in it, and if they hook up, vapor!   I’m not sure about higher states of matter for water though, I’d assume if it’s over 100c it’ll be vapor for a very long time?  Would the bonds hold up at these temps?

Link to comment
Share on other sites

A quick search suggests that at the 3000k typical of a red dwarf the reaction to form water from H2 and O2 will be in an equilibrium with roughly equal equal quantities of each gas.

Link to comment
Share on other sites

On 5/3/2023 at 2:46 AM, tomf said:

A quick search suggests that at the 3000k typical of a red dwarf the reaction to form water from H2 and O2 will be in an equilibrium with roughly equal equal quantities of each gas.

Its been a while since high school chemistry for me, do you mean an equilibrium reaction, or am I misunderstanding you?

 

Edit: My google-fu isn't as good as yours, I keep getting results for rocky planets with water orbiting a red dwarf.

Edited by Meecrob
Link to comment
Share on other sites

5 hours ago, Meecrob said:

Its been a while since high school chemistry for me, do you mean an equilibrium reaction, or am I misunderstanding you?

It's been a while for me too, but my recollection is that all reactions are equilibrium reactions even if the equilibrium constant is extremely large or small. And that increasing the temperature for an exothermic reaction pushes the reaction to the reverse.

Link to comment
Share on other sites

Hopefully this is a good topic to stick this into. Just recently there was a bit of a talk about the JWST discovering "problems with physics." There's now convincing research on what's going on, and this is a very good video explaining it in simple terms.

 

Link to comment
Share on other sites

11 hours ago, K^2 said:

problems with physics

At work so I can't watch it.  Was the talk about problems with physics or the Crisis in Cosmology (Webb is seeing complex structures at a presumed age where many expected immature systems)? 

I've seen nothing credible that Webb is challenging physics, but several recent papers claiming our understanding of the early universe needs work. 

Link to comment
Share on other sites

I use YT transcription services for getting a quick summary of most videos.

"Our theories need updating" is about right. If I read the transcript correctly, they haven't learned as much as was hoped about Cold Dark Matter affecting expansion but will have to tweak the software that assumes the initial mass function of the Universe.

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...