The James Webb Space Telescope

[pinball1970]

I had a quick search on Webb for updates on that issue with MIRI

I did not find anything.

This image was on the site though, “Webb Reveals Shells of Dust Surrounding Brilliant Binary Star System.”

What is this top right? It looks very symmetrical in shape and colour, just an optical effect from the telescope like diffraction spikes?

 

[sophiecentaur]

just an optical effect from the telescope like diffraction spikes?

You may be right but if the effect is being introduced locally (to the telescope) then what could be special about the light from the star? It doesn't occur for other stars.
The effect seems to be a rare one.
Those regular fringes extend over millions of km, if we assume they're actually around the star. There's nothing that uniform around a star so if it were 'waves of ejecta', due to regular explosions, the spacing would change with distance unless the speeds are colossal and the star's gravity is having negligible effect. A series of images, over a long period, could reveal motion but wouldn't that require a very long timescale?

 

[Borg]

just an optical effect from the telescope like diffraction spikes?

Maybe dust from the main star being imaged? The other stars may be in front of the dust.

 

[sophiecentaur]

Maybe dust from the main star being imaged? The other stars may be in front of the dust.

Possibly but no apparent colour fringes and the star is not monochromatic.
Weird.

 

[pinball1970]

Holy moly...I was looking for another picture with the weird object and this was on the front.

https://www.nasa.gov/feature/goddar...s-star-filled-portrait-of-pillars-of-creation

 

[pinball1970]

Side side with Hubble on the left from 2014
I turned on all the lights off in the office so I could see this in all its glory.
Wow.

 

[hutchphd]

Weird.

Perhaps I am reading tea leaves. The hexagonal pattern is obviously from the optics (likely the mirror shape) but to my eye the green shape is rotated 30^o relatve to the red one. I having trouble figuring a plausability argument for that, either diffraction or refraction. One also should be cognizant that these are false colors.

 

[sophiecentaur]

But why aren’t all (bright) star images like it?

 

[hutchphd]

But why aren’t all (bright) star images like it?

My best guess (I just thought of it) is that it looks like the internal "camera" reflection from either the bright object in field or perhaps one just out of field off axis. I don't know enough about Webb optics to be any more definitive

 

[pinball1970]

My best guess (I just thought of it) is that it looks like the internal "camera" reflection from either the bright object in field or perhaps one just out of field off axis. I don't know enough about Webb optics to be any more definitive

I tried blowing up some of the other objects but they all were too blurred.

 

[anorlunda]

Is there a NASA source to get such images with full resolution?

 

[berkeman]

I tried blowing up some of the other objects

Did you borrow Peter's blaster again? I thought we already had "the talk" about that...

https://www.deviantart.com/nocturnbros/art/Marvin-the-Martian-invades-DEATH-BATTLE-683673659

 

[pinball1970]

Is there a NASA source to get such images with full resolution?

The image is from the NASA site. I have been looking at other images and cannot see anything like this.
Dust has been mentioned, if it is fairly evenly distributed then could the rings which look almost concentric cause that effect via some sort diffraction?

 

[Devin-M]

https://www.sciencealert.com/jwst-captures-incredible-images-of-dust-being-pushed-by-light

 

[pinball1970]

https://www.sciencealert.com/jwst-captures-incredible-images-of-dust-being-pushed-by-light

Scroll up dear friend, scroll up.

 

[sophiecentaur]

some sort diffraction?

But there are no coloured edges and you don't get diffraction effects from massive objects (i.e. out in space). Diffraction would have to be taking place the telescope optics and would apply to many images of the appropriate brightness.

The explanation that it's due to ripples in dust, caused by regular pulses of light certainly gets my vote. 1. Regular pattern. 2. No colour effects. 3. The fact that it's a rare effect indicates some very high energy involved.

 

[Filip Larsen]

https://arxiv.org/abs/2210.10074
with a nice write-up by John Timmer at
https://arstechnica.com/science/202...ed-from-galaxies-11-billion-light-years-away/

New Webb images illuminate the formation of a galaxy cluster​

A team of researchers is publishing a paper based on new images taken by the Webb Space Telescope. The images reveal a dense concentration of matter in the early Universe, potentially indicating early stages in the formation of a galaxy cluster. And thanks to the spectrograph present, Webb was able to confirm that several galaxies previously imaged by Hubble were also part of the cluster. It even tracked the flow of gas ejected by the largest galaxy present.

 

[berkeman]

Thread is closed temporarily for Moderation (and possible thread split to break off the side-discussion about diffraction effects in telescopes)...

 

[berkeman]

Okay, thread is reopened. New thread on diffraction effects in telescopes is here: https://www.physicsforums.com/threa...rtifacts-in-telescopes-like-the-jwst.1047305/

Let's try to keep this thread about JWST news and specific items. Thanks.

 

[Filip Larsen]

https://esawebb.org/news/weic2219/?lang :

The NASA/ESA/CSA James Webb Space Telescope has revealed the once-hidden features of the protostar within the dark cloud L1527 with its Near Infrared Camera (NIRCam), providing insight into the formation of a new star. These blazing clouds within the Taurus star-forming region are only visible in infrared light, making it an ideal target for Webb.

 

[pinball1970]

They have fixed the issue with MIRI apparently. Nothing on the NASA site though.

 

[mfb]

Analysis of micrometeorite impacts shows that the May event was likely really bad luck and should stay an outlier instead of a regular occurrence.

 

[sophiecentaur]

Which one of those two guys actually threw the test brick? It would certainly be a CV item for him.

 

[BillTre]

Make your own JWST.

 

[pinball1970]

Make your own JWST.

Not sure how I missed this. Brilliant.

I was looking for updates on the NIRISS glitch and came across this.

https://www.quantamagazine.org/astronomers-say-they-have-spotted-the-universes-first-stars-20230130/

with the associated paper.

https://arxiv.org/abs/2212.04476

EDIT: Preprint

 

[pinball1970]

It looks like Webb has recovered from the NIRRIS glitch

https://www.stsci.edu/contents/news/jwst/2023/niriss-has-returned-to-science-operations

 

[pinball1970]

ESA have released this of Uranus
https://esawebb.org/videos/weic2310a/

Better than the Voyager 2 fly by images? I would have thought being very close with a good camera would still have the better of being much further away with an amazing camera.

https://en.m.wikipedia.org/wiki/Exploration_of_Uranus

 

[Vanadium 50]

I don't understand why they felt compelled to make a video of a still image/

"Better"? It's in different wavelengths. Is green better than red? Or blue?

 

[pinball1970]

"Better"? It's in different wavelengths. Is green better than red? Or blue?

Resolution, detail.

 

[Vanadium 50]

Uranus is pretty featureless. The rings seem to come out better, but that doesn;t surprise me in the IR.

 

[BWV]

Uranus is pretty featureless. The rings seem to come out better, but that doesn;t surprise me

…please let me resist temptation for bad joke …

 

[Vanadium 50]

The opportunities for Uranus jokes are...ahem...endless. And besides jokes, there is...inuendo.

Should I go on?

 

[sophiecentaur]

I don't understand why they felt compelled to make a video of a still image/

Standard way of getting good planetary images. They aren't short of light with a big scope (or even a home one) so a large set of sequential images allows software to reject bad ones, re-position the selected images and then stack them. It's better than plain stacking of a few long exposures. Also, the contrast range will be a lot les for a planet than for galaxies and nebulae so it's a very different job altogether. "It's a very different job."!!
There are pros and cons about flyby images vs Hubble images. Hubble can spot changes where a brilliant flyby image just shows things as they are - once in decades.

 

[Vanadium 50]

No, what I don'y understand is why they took a picture and then put the picture on Youtube,. Why not just post the picture, a la APOD. Or is that so 20th century?

 

[sophiecentaur]

No, what I don'y understand is why they took a picture and then put the picture on Youtube,. Why not just post the picture, a la APOD. Or is that so 20th century?

Oh, right. That sort of presentation is reckoned to be more sexy, I think. Screen saver stuff. But the image is not very special in the first place.