# Are blue and red shift visible?

When looking into the sky at night using my bare eyes, I see that stars appear in different colors. From my understanding this is caused by different chemical compositions of those stars which show up in their spectral lines and therefore defining their color.

Does blue and red shift visibly change the color perception when looked at the stars with your naked eye?

As James K says, it is not possible with the naked eye. But in fact, it almost is. The quasar CTA 102 lies at a redshift of $z\simeq1$ and usually has an apparent magnitude of +17. Very recently (within the last few months) it had a bright outburst, increasing its magnitude to +11.5, i.e. more than two orders of magnitude in brightness! This is still not visible with the naked eye, but a colleague of mine just photographed it with a regular camera. A 10 sec exposure with no tracking makes it barely visible, but a 30 sec exposure, piggybacking on a telescope for tracking the sky, displays a beautiful reddish dot.