You're confusing 2 different but related concepts. Blueshift and redshift does depends only on velocity. In the cosmological sense, redshift (the opposite of blueshift) occurs because everything is moving away from everything else due to the expansion of the universe, and so the distance of an object can be calculated based on how much redshift there is in the light. Basically, on a cosmological scale, distance and velocity are connected
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
replies: