I love to see the curiosity. The red stars (which are galaxies, stars are very small comparatively), are red because they are moving away from us in space-time. This is called the doppler effect and the blue galaxies are moving towards the telescope. The whole color adjustment thing is purely up to the person rendering the data. For example, if the scientists wanted to color the JWST to a more realistic color (like the Hubble), all they would need to do is adjust it. You can also safely assume that most of these types of renderings are in a false color because of how the telescopes receive data and how we render them.
I'd like to add that some of the blue ones could actually be stars, but stars in our own galaxy that happen to be in between us and the galaxy. Most would still be galaxies at least, though.
Yes! Thank you! Most of the stars that you’d see in our galaxy would have the trademark JWST refraction spikes. That’s (generally) the best way to tell if the star is in our local region.
Is it possible they have their colors because of their composition of stars? For example one is blue because it is full of mostly very hot stars? Or is it that the Doppler effect largely overpowers any underlying color bias
On this scale the Doppler will/would always prevail. These galaxies are millions, or even billions of light years away. If you look at Hubble's photo of this galaxy, you don't see any of those colors, and Hubble is in full spectrum light (visible). While JWST is infrared. I'm taking an educated guess as to why we see greens, and other colors such as purple; it would likely be artifacts, or some other data rendering effect. Perhaps those galaxies are full of hotter stars like you had mentioned. It could be some other celestial phenomenon that could produce large, and I mean LARGE amounts of energy to change the colors from the Doppler shift. Which would only be visible in the radiation spectrum that's ejected. They would only really be visible in the x-ray, and/or infrared. EG: a hypernova/supernova, neutron star mergers, black hole mergers, etc. Unfortunately, with the expansion of the universe moving faster than light, the Doppler would still cause a red-shift for galaxies waving good-bye, and blue-shifts for galaxies saying hello. So, I truly doubt it's anything but artifacts from data rendering. I should note that I'm not an astrophysicist, this is a hobby for me. Maybe there are scholarly journals out there that can explain the shifts in color.
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u/ieatbabies92 Nov 25 '24
I love to see the curiosity. The red stars (which are galaxies, stars are very small comparatively), are red because they are moving away from us in space-time. This is called the doppler effect and the blue galaxies are moving towards the telescope. The whole color adjustment thing is purely up to the person rendering the data. For example, if the scientists wanted to color the JWST to a more realistic color (like the Hubble), all they would need to do is adjust it. You can also safely assume that most of these types of renderings are in a false color because of how the telescopes receive data and how we render them.