Recent content by feddz

  1. feddz

    Undergrad How do we measure expansion if we see distant galaxies in the past?

    If the galaxies we see are as they were a few million years ago, then how do we know that the universe is expanding since we don't know their current velocities? Hubble's graph shows a linearly proportional relationship between velocity and distance but the fact that the further a galaxy is, the...