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NASA released this image of deep space. The way light shifting vis-a-vis universe expansion is supposed to work is by making the furthest galaxies appear mostly red-shifted. But NASA's image shows somewhat of an even balance between blue and red shift. Why is that?

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You cannot gauge the redshift of a galaxy by looking at a false colour image. The images taken through different filters are stacked and colourised to suit. You can say that the blue galaxies are indeed bluer than the red galaxies, but there is no absolute scale with which to judge redshift by eye.

Secondly, there is no detail in the NASA web page, but the ACS and WFC3 cameras have near infrared capabilities. So I would think that this image is a visual false-colour image of information that extends well redward of what the eye can perceive. So even the things that look blue might have a spectrum that peaks at redder wavelengths, whilst anything that looks red might actually be infrared!

However, beyond this, in order to judge what the redshifted appearance of a galaxy would be, you would need to know what the galaxy looked like with zero redshift. That is, light that is emitted in the ultraviolet could be redshifted into the visible part of the spectrum. It is entirely possible that visual colour of a redshifted galaxy would not change very much at all if the galaxy emitted lots of UV light in its frame of reference or equally, if it emitted lots of very red light that was then redshifted out of the telescope's sensitivity range.

Finally, there could be some genuine astrophysics going on. Many distant galaxies are bluer than nearby galaxies because they are undergoing intense star formation. Massive star forming regions emit copious UV light that is redshifted into the optical.

Finally, finally! Many of the galaxies in the picture will be quite close and will not be very redshifted.

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There are two factors here.

First, to construct an image such as this, several optical filters are used, and then these are then merged to give an image. The colours that you see are therefore not the "true" colours (they couldn't be, the light you see is far too faint for the human eye) but are chosen to bring out details in the image. A galaxy that is blue in the image might not actually be blue.

Secondly, red shift means that all the light is shifted, If a galaxy is emitting a broad spectrum of light, the ultraviolet is shifted to the visible, as the red is shifted to the infrared, the apparent colour doesn't change much. So the apparent colour, red or blue isn't telling you about the red-shift of each galaxy.

To measure the red shift you need a detailed spectrum. A spectrum will include spectral lines, which have known frequencies. By noting the shift of these lines the redshift is measured.

The different colours you see here are probably a consequence of the type of stars in each galaxy. Galaxies with more young stars appear bluer, and this is probably emphasised in the image (but remember it isn't "true colour")

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I used image search to find a version with more detail (Google Image Search is great for this sort of thing) about how it was taken, the RGB channels in the mage were taken with IR, Visual, and Blue filters respectively.

The main galaxy cluster in it, Abel 2744, is only at a red-shift of 0.3; so it's colors aren't that far removed from what we could see visually (with much better eyes).

Also, just looking at the picture doesn't give you any way to tell the difference between a galaxy that's relatively near but dim or much farther but bright. However I suspect a majority of the tiny blue galaxies are smaller members of Abel 2744 not extremely distant objects that would need a major blue shift to cancel the red shift from ex.

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