The BBC site has similar with their own analysis:
James Webb Telescope: Nasa reveals new images of distant cosmos - BBC News
James Webb Telescope: Nasa reveals new images of distant cosmos - BBC News
James Webb space telescope set to launch on Christmas Eve.
- Thread starter Gingerbread Demon
- Start date
Vox's article includes an A/B comparison of the galaxy cluster image released yesterday with an observation Hubble made of the same spot. I tried to find out some details on the Hubble image. I didn't get anything solid, but it looks like it's not a perfectly fair comparison, the Hubble photo is only a half-hour total exposure, compared to Webb's twelve hours, but the details are still sharper in Webb's image than in other, much longer Hubble photos.
Of course, the JWST images also mostly show the near IR and not the full optical spectrum captured by the HST. Any images that are made public are therefore somewhat artificial in that colours have been assigned manually to bring out details. The angular resolution in the red optical region are significantly better than HST because of the larger effective aperture of the JWST.
Yeah, looks like the HDF. So what, right?
Well the biggest bombshell I saw in the above NASA video release was the ability of WEBB to examine the atmospheres of EXOPlanets in extreme detail.
The shown example was of an EXOP with quite a bit of O2 present, and I don't need to state the importance of that.
What I am now waiting for is spectrum from EXOPs which match or are close, one way or the other, to our own.
Huge potential to see civilizations industrially similar to our own.
Well the biggest bombshell I saw in the above NASA video release was the ability of WEBB to examine the atmospheres of EXOPlanets in extreme detail.
The shown example was of an EXOP with quite a bit of O2 present, and I don't need to state the importance of that.
What I am now waiting for is spectrum from EXOPs which match or are close, one way or the other, to our own.
Huge potential to see civilizations industrially similar to our own.
I'd like them to look for phosphine on worlds with a simililar temp/composition of Venus. Until more is known of what's caused that reading on Venus itself, it would be interesting to know if that is semi-common.
What's going to be really interesting is when they have Webb focus on things in our own solar system. What kinds of new stuff will we learn about our own system of planets? Content of the extreme edges past Pluto, and objects closer in we didn't know about yet. I'm pretty sure one target will be Titan and it's atmosphere. If there was ever an instrument that could find large planet sized objects in the outer reaches of the solar system, it'll be Webb.
Yeah, it'd be good to check whether the object supposedly spotted in old IRAS data really is planet 9 or just noise.
[2111.03831] A search for Planet 9 in the IRAS data (arxiv.org)
People stating that those images are false color images is misleading.
Yes, the raw data is from outside the visible spectrum and therefore needs color adjustment in an image representation.
but the colors are not arbitrary.
One of the main reasons Webb is imaging in IR is to capture light that has been redshifted out of the visible range by space time expansion.
But that light used to be visible billions of years ago/billions of ly away.
The telescope sensors use filters that correspond to RGB and other visible spectra, and the colors are shifted back to what they used to be.
so what we see is accurately mapped to the original wavelengths.
Now, this is for deep sky obviously.
when it comes to relatively near objects like the nebulas or even the Stephan‘s Quintet galaxies, it‘s a different story.
There we take advantage of IR light to penetrate the dense dust clouds and get an insight look.
Here you are correct that false colors are used to create a higher color contrast for our human perception and reveal stuff that is and always has been utterly invisible to us otherwise.
Yeah, not arbitrary. I'll repeat what I typed previously in this thread:
Only the wavelength range from 0.6 μm to 0.74 μm overlaps with what humans can see. Therefore, colours depicted in Webb images are artificial. The colours are chosen to enhance detail to our eyes as you state. This is done for all the images - whether deep field or otherwise. Such processing isn't unique to the JWST - almost every modern astronomical image you see is heavily processed in some way. That the original spectra are available for each object in the image is the important part for the science.
Only the wavelength range from 0.6 μm to 0.74 μm overlaps with what humans can see. Therefore, colours depicted in Webb images are artificial. The colours are chosen to enhance detail to our eyes as you state. This is done for all the images - whether deep field or otherwise. Such processing isn't unique to the JWST - almost every modern astronomical image you see is heavily processed in some way. That the original spectra are available for each object in the image is the important part for the science.
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True. Arguably, this is not restricted to science.
Pretty much every modern camera does this automatically without us even noticing usually.
Even a simple white balancing before we press the trigger already is done for the same reason.
and then post processing in a slightly more advanced level, including clipping, re-distribution of color and luminance values, etc.
Don‘t have to go to space telescopes to find this…
Pretty much every modern camera does this automatically without us even noticing usually.
Even a simple white balancing before we press the trigger already is done for the same reason.
and then post processing in a slightly more advanced level, including clipping, re-distribution of color and luminance values, etc.
Don‘t have to go to space telescopes to find this…
Even humans don't agree about what is in front of our eyes - hence the white/gold or blue/black dress meme from a few years ago.
Yeah, that image was not properly white balanced at all.
But then again, even if it were, placing it I to a context with different color temperature, it would immediately look wrong again.
Apparently, the dress really was black and blue. I've seen a different picture of it but I could never see the original as anything other than gold and white. In reality, all qualia are arbitrary. There's no guarantee that any of us experiences the world as any other person does. We assume that we do but the dress example suggests perhaps that is not the case.
Funny that YT suggested this to me right now.
Farthest Galaxy yet seen. 10.1 billion ly's.
https://www.nationalgeographic.com/adventure/article/150506-most-distant-galaxy-astronomy-space
https://www.nationalgeographic.com/adventure/article/150506-most-distant-galaxy-astronomy-space
Actually, the article is slightly incorrect. That galaxy is much farther away than 13.1 billion light years due to the expansion of the universe. The visible universe is about 92 billion light years in diameter so the galaxy would "now" be about 45 billion light years away and that is how far the light has travelled. We are seeing the galaxy as it was 13.1 billion years ago.
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as the universe ages, eventually future astronomers on some far future planet will only see their own galaxy. they'll eventually work out the scientific knowledge that there should be others, presumably, and maybe one of the great scientific triumphs for them will be catching the image of some lonely rogue star passing through the intergalactic void, but they'll never be able to see them. of course we can only see visible matter now, and not all of that, so it's not so different.
If the expansion of the universe continues to accelerate, everything within it might be destroyed in a big rip anyway according to some speculations.
Also Anton's video is worth watching:
