Why do galaxies have colors?

Blue: is the region of many young stars, in high mass stars live fast and die young, it is caused by the radiation.

Red: is caused when low-frequency light. The color of galaxies is affected by the distance. The colors of most galaxies are red or pink.

Redshift and Blueshift: is how light changes as objects in space (such as stars or galaxies) that move farther or closer to us.