• Question: What can astronomers conclude based on the observed red shifts in the spectral lines of distant galaxies?

    Asked by bhavinamistry to Davie, Gemma, James P, James V, Nuala on 28 Jun 2012.
    • Photo: James Verdon

      James Verdon answered on 28 Jun 2012:

      Hi bhvinamistry,
      The red shift indicates that all the galaxies are moving away from us. If everything is moving away from each other, we must have once been together. This is part of the evidence for the big bang – we were all initially together at the beginning of the universe, then the big bang happened, the universe started expanding and we all started moving apart.

    • Photo: James Pope

      James Pope answered on 28 Jun 2012:

      Hi bhavinamistry,

      James V has pretty much answered it all, but I’d add that (I think) the conclusion from red shift is that these galaxies are still moving away from us, so the Universe is continuing to grow!

      This is also the second time today that I have been asked his question! I was asked this in a school I was visiting today to talk about science and science careers!

Comments