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Downvote me to hell, but as a person who has zero understanding of what differentiates Hubble from Webb, the pictures alone just aren't doing it for me. I was excited to see something completely new given 30 years and 10 billion dollars and instead I feel like I'm seeing what looks like an enterprise upgrade and feel slightly disappointed. What am I missing?
Downvote me to hell, but as a person who has zero understanding of what differentiates Hubble from Webb, the pictures alone just aren't doing it for me. I was excited to see something completely new given 30 years and 10 billion dollars and instead I feel like I'm seeing what looks like an enterprise upgrade and feel slightly disappointed. What am I missing?
These are just the first few images. Give it time.
What JWST can do is show new things that have never been seen before, but obviously it's a bit hard to schedule that sort of photos.
Earlier quoted context omitted.
It's all IR. It's color-mapped over RGB, but the sensors are IR.
Didn't the observed light shift into IR wavelengths due to the expansion of space over the last billions of years while it traveled to us? Do the recolored images have any relation to what the original view would have looked like, or is it just arbitrary "artistic license"?
They did not release or talk in much technical detail of how the images were assembled, which I'm sure will be done at some point.
I do not think the colors do correspond (at least not deliberately), for 2 reasons:
First is that the image of the Deep Field ("SMACS") contains galaxies at a range of redshifts. For example there may be galaxies quite near us (redshift z = 0 or close to 0) while others are more distant (the arced galaxies in the image being lensed that this image is famous for, at redshift z = 0.39), where redshift is the measure (1+z) of how much the wavelength light has been multiplied.
So regardless of what color mapping you chose, it would not be a perfect fit for all objects in the field of view. For the galaxies near us in the image (z=0), the wavelengths being converted to RGB don't correspond to what we would see in the optical.
Secondly, if it were remapped especially for the galaxy cluster of interest in this image, I don't think the colors are specifically tuned for that either.
In more detail:
Consider the optical color spectrum we see, ROYGBIV, or let me reverse it in order of increasing wavelength VIBGYOR -- and take the "RGB" 3 colors that might make up an image, or BGR to use that ordering -- this spans a wavelength range of say 400nm, 600nm, 800nm.
The imaging filters available on the NIRCam span 900nm to 4400nm (4.4 micron) and there are 29 of them [0]. Researchers choose which filters to use based on what they wish to study. And recall that the imaging sensor actually outputs grayscale only, it is the filters that give it a color view and individual images in each filter are assembled to create a color composite.
According to an example science program designed to take such images[1], the filters selected to be imaged might be 900nm, 1150nm, 1500nm.
If you applied the redshift of the galaxies (divide by 1.39 from the above info about the cluster of galaxies), the above sampled wavelengths in the image would still correspond to redder parts of the spectrum compared to what is visible if we were seeing the galaxies now: 647, 827, 1079nm.
So, no I don't think the color mapping was chosen to be accurate in a scientific sense of seeing what you would see if the galaxies were brought to the "original" view.
[0] https://jwst-docs.stsci.edu/jwst-near-infrared-camera/nircam...
[1] https://jwst-docs.stsci.edu/jwst-near-infrared-camera/nircam... ("select filters")
For the professional (or former professional) astronomers among us, I will make my somewhat amused observation that what people are most paying attention to is not really the distinguishing features of JWST. People seem most impressed by the apparent increase in resolution of the images, which is not from a certain point of view the hardest thing to do . HST might have done that if its instruments had been of differe…
If I may get political here (nothing personal / no direct reply to the parent comment): > stunning images was enough to get the public to support a $10B project. I don't believe public support is relevant; is there public support for the >$700B a year spent on the military?
Global force projection at the benefit for all Western economies is very expensive. This money is required to even allow the form of economy "the West" is running.
How else were you going to keep up the Pax Americana that enables globalization by making significant global trade networks even possible in the first place? Who's gonna insure your freighter if international waters aren't protected by Western navies? Pirates, rogue states closing important channels, at will seizures for no reason... the list is long.
As the Pax Americana will likely soon fade through growing influence of the BRICS nations and "America First"-style ideologies, the 700B will probably wither away quite fast in the next decades - along with all the benefits we enjoyed since WW2.
Just one illustration. How man South American or African nations support the sanctions against Russia? How many Asian nations that are not Japan?
Earlier quoted context omitted.
Quoted post unavailable.
I think this is a little harsh, but I actually generally agree. I'm a total laymen here and my PRIMARY TAKEAWAY has been the IR component and how much more and further away you can see because of it.
Earlier quoted context omitted.
Didn't the observed light shift into IR wavelengths due to the expansion of space over the last billions of years while it traveled to us? Do the recolored images have any relation to what the original view would have looked like, or is it just arbitrary "artistic license"?
Hey, that's an interesting and uncommon question that I had not seen elsewhere -- They did not release or talk in much technical detail of how the images were assembled, which I'm sure will be done at some point. I do not think the colors do correspond (at least not deliberately), for 2 reasons: First is that the image of the Deep Field ("SMACS") contains galaxies at a range of redshifts. For example there may be gal…
At this point I like it even for just brightening the news cycle anyway.
It might be because of a different post-processing algorithm, or some phi-related magic, just curious a bit.