Something has been bugging me all day.
My understanding of redshift is that as space expands between two objects, the wavelength of the light wave is stretched causing it to appear redder, because it is getting closer to the redder end of the visible spectrum.
Assuming that this expansion affects all wavelengths, I can understand that all visible light from a star/galaxy will appear redder by the time it gets to us. But doesn't this also mean that waves in the ultra-violet spectrum would also be redshifted into visible light?
And if this was the case, wouldn't that mean the object would not appear redder at all?
Please don't hesitate to embarrass me if I am missing something extremely simple here.