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Gravitational lensing. From the description[0]: Other features include the prominent arcs in this field. The powerful gravitational field of a galaxy cluster c

Gravitational lensing. From the description[0]: Other features include the prominent arcs in this field. The powerful gravitational field of a galaxy cluster can bend the light rays from more distant galaxies behind it, just as a magnifying glass bends and warps images. Stars are also captured with prominent diffraction spikes, as they appear brighter at shorter wavelengths. [0] https://webbtelescope.org/contents/news-releases/2022/news-2022-035?Collection=First%20Images https://webbtelescope.org/contents/news-releases/2022/news-2...

rootusrootus 4y ago
Ah, that makes perfect sense. I guess I should have RTFM rather than just gawk at the pictures. Thanks for the ELI5!
- russh 4y ago
  Oh, that makes sense. I was wondering about the odd shapes.
samstave 4y ago
So, would that mean that the gravitational lensing over how-ever-many-light-years is ALSO coupled with the convex/cave aspect of the pico-adjusting of the JWT 'lens' such that even our JWT's pico-adjustments affect the NORMAL of the photons to the image? Can this be adjusted for? Wouldnt the pico-arc of the overall array affect the image output due to the distances involved such that we receive "false gravitational lensing, simply based on distance from the sensor" ? I wonder if a more precise version(s) of the hex lenses could be made such that they can 'normal-ize' on a much more refined basis. I know that each JWT is already capable of mico-flexes to each cell... but if we can develope an even further refinement (Moores law on the JWTs hex lenses resolution) we will be able to make thousands of images with varying the the normalization to each receiving area and comparing image quality. Also, I am sure there are folks who know the reflective characteristics of photons from each wavelength that would allow for orientations for each wavelength. -- Do ALL 'light' wavelengths, particles bounce off the reflector materials in the same way? - meaning do infra waves/photons bounce in the exact same way as some other wavelength with the exact same orientation of the sensor? --- Do they do any 'anti-gravitational-lensing' correction calcs to 'anti-bend' a photons path to us to 're-normalize' the path that we should have seen? Whats the current science behind such?
- qwertywert_ 4y ago
  The gravitational lensing matches exactly how it looked in Hubble's deep field overlay, so I would guess no the JWST lens is not causing any "false" gravitational lensing? If that's what you are asking.
  - samstave 4y ago
    Thanks! I worded that poorly ; Wouldn't one be able to adjust the perceived path of the photon after time, to adjust for re-normalizing the path of the photon based on the understanding of the gravitational arc imposed on such -- meaning the astro equivalent of "ZOOM. ENHANCE!" :-)
    - qwertywert_ 4y ago
      Ah right, good question yes it seems like it could be possible..
      - samstave 4y ago
        The normalization I was thinking of was : Lets assume you have a 'straight' vector of line of sight pointing your Earthly-Bound-Lens [hubble/jswt/whatever] at the object of interest. you also have an idea through previous observations of gallaxies on the line of sight, which will have gravitational impact on the trajectory of the photons of interest... the arrival photon's wiggle represents a wobble in time to get to earth. Meaning it changed phase multiple times between our sensor receiving it, and its origin. If one could look at the path and the grav-lenses it went through, one may be able to extrapolate a more clear picture at various distances(times)....??? /r/NoStupidQuestions ( I am picturing a straight shot - but the photon traveled between many other celstials - and those
    - 8note 4y ago
      Depending on the orientation, you wouldn't have the right pixels to put for the angle of view from straight on. Eg, you'd normally see the side view of an object, but the lensing gets you the top and bottom views
april_22 4y ago
Will the JWST be able to make photos of black holes, similar to the ones the EHT made? And if yes, can the JWST be used to study black holes?
- nullc 4y ago
  Producing an "image" of a black holes requires astronomical, ahem, resolution because they're so far away (thankfully). To achieve this kind of resolution you need an aperture of thousand of kilometers. The EHT images are created using synthetic aperture techniques to create an effective aperture with a diameter of earth's orbit around the sun. But this is only currently possible at radio frequencies due to our ability to capture, store, and coherently combine the phase information. It's essentially SDR beam forming across space and time. We can also study black holes though visible and IR observations through their effects of the things around them-- lensing from their mass, matter heated up by falling in. Here is an image I took of the relativistic speed matter jet believed to originate from black hole in M87: https://nt4tn.net/astro/#M87jet https://nt4tn.net/astro/#M87jet ... and Webb can do a lot better than I can with a camera lens in my back yard. :) Aside, there is some controversy about the EHT black hole images. A recent paper claims to be able to reproduce the ring like images using the EHT's imaging process and a simulated point source-- raising the question of the entire image just being a processing artifact. https://telescoper.wordpress.com/2022/05/13/m87-ring-or-artefact/ https://telescoper.wordpress.com/2022/05/13/m87-ring-or-arte... Though it's not surprising to see concerns raised around cutting edge signal processing-- LIGO suffered from a bit of that, for example, but confidence there has been improved by a significant number of confirming observations (including optical confirmations of ligo events).
  - april_22 4y ago
    Thank you! Another question: are they already planning a successor to JWST? Is something better even possible? If it took more than 30 years, we should start sooner than later :)
    - ceejayoz 4y ago
      https://en.wikipedia.org/wiki/List_of_proposed_space_observatories https://en.wikipedia.org/wiki/List_of_proposed_space_observa... https://en.wikipedia.org/wiki/SAFIR https://en.wikipedia.org/wiki/SAFIR is the closest to a proposed JWST successor; the others largely serve different purposes.

rootusrootus 4y ago

Ah, that makes perfect sense. I guess I should have RTFM rather than just gawk at the pictures. Thanks for the ELI5!

russh 4y ago
Oh, that makes sense. I was wondering about the odd shapes.

samstave 4y ago

So, would that mean that the gravitational lensing over how-ever-many-light-years is ALSO coupled with the convex/cave aspect of the pico-adjusting of the JWT 'lens' such that even our JWT's pico-adjustments affect the NORMAL of the photons to the image? Can this be adjusted for? Wouldnt the pico-arc of the overall array affect the image output due to the distances involved such that we receive "false gravitational lensing, simply based on distance from the sensor" ? I wonder if a more precise version(s) of the hex lenses could be made such that they can 'normal-ize' on a much more refined basis. I know that each JWT is already capable of mico-flexes to each cell... but if we can develope an even further refinement (Moores law on the JWTs hex lenses resolution) we will be able to make thousands of images with varying the the normalization to each receiving area and comparing image quality. Also, I am sure there are folks who know the reflective characteristics of photons from each wavelength that would allow for orientations for each wavelength. -- Do ALL 'light' wavelengths, particles bounce off the reflector materials in the same way? - meaning do infra waves/photons bounce in the exact same way as some other wavelength with the exact same orientation of the sensor? --- Do they do any 'anti-gravitational-lensing' correction calcs to 'anti-bend' a photons path to us to 're-normalize' the path that we should have seen? Whats the current science behind such?

qwertywert_ 4y ago
The gravitational lensing matches exactly how it looked in Hubble's deep field overlay, so I would guess no the JWST lens is not causing any "false" gravitational lensing? If that's what you are asking.
- samstave 4y ago
  Thanks! I worded that poorly ; Wouldn't one be able to adjust the perceived path of the photon after time, to adjust for re-normalizing the path of the photon based on the understanding of the gravitational arc imposed on such -- meaning the astro equivalent of "ZOOM. ENHANCE!" :-)
  - qwertywert_ 4y ago
    Ah right, good question yes it seems like it could be possible..
    - samstave 4y ago
      The normalization I was thinking of was : Lets assume you have a 'straight' vector of line of sight pointing your Earthly-Bound-Lens [hubble/jswt/whatever] at the object of interest. you also have an idea through previous observations of gallaxies on the line of sight, which will have gravitational impact on the trajectory of the photons of interest... the arrival photon's wiggle represents a wobble in time to get to earth. Meaning it changed phase multiple times between our sensor receiving it, and its origin. If one could look at the path and the grav-lenses it went through, one may be able to extrapolate a more clear picture at various distances(times)....??? /r/NoStupidQuestions ( I am picturing a straight shot - but the photon traveled between many other celstials - and those
  - 8note 4y ago
    Depending on the orientation, you wouldn't have the right pixels to put for the angle of view from straight on. Eg, you'd normally see the side view of an object, but the lensing gets you the top and bottom views

april_22 4y ago

Will the JWST be able to make photos of black holes, similar to the ones the EHT made? And if yes, can the JWST be used to study black holes?

nullc 4y ago
Producing an "image" of a black holes requires astronomical, ahem, resolution because they're so far away (thankfully). To achieve this kind of resolution you need an aperture of thousand of kilometers. The EHT images are created using synthetic aperture techniques to create an effective aperture with a diameter of earth's orbit around the sun. But this is only currently possible at radio frequencies due to our ability to capture, store, and coherently combine the phase information. It's essentially SDR beam forming across space and time. We can also study black holes though visible and IR observations through their effects of the things around them-- lensing from their mass, matter heated up by falling in. Here is an image I took of the relativistic speed matter jet believed to originate from black hole in M87: https://nt4tn.net/astro/#M87jet https://nt4tn.net/astro/#M87jet ... and Webb can do a lot better than I can with a camera lens in my back yard. :) Aside, there is some controversy about the EHT black hole images. A recent paper claims to be able to reproduce the ring like images using the EHT's imaging process and a simulated point source-- raising the question of the entire image just being a processing artifact. https://telescoper.wordpress.com/2022/05/13/m87-ring-or-artefact/ https://telescoper.wordpress.com/2022/05/13/m87-ring-or-arte... Though it's not surprising to see concerns raised around cutting edge signal processing-- LIGO suffered from a bit of that, for example, but confidence there has been improved by a significant number of confirming observations (including optical confirmations of ligo events).
- april_22 4y ago
  Thank you! Another question: are they already planning a successor to JWST? Is something better even possible? If it took more than 30 years, we should start sooner than later :)
  - ceejayoz 4y ago
    https://en.wikipedia.org/wiki/List_of_proposed_space_observatories https://en.wikipedia.org/wiki/List_of_proposed_space_observa... https://en.wikipedia.org/wiki/SAFIR https://en.wikipedia.org/wiki/SAFIR is the closest to a proposed JWST successor; the others largely serve different purposes.