• Question: what have you learnt about celestial bodies in the early universe?

    Asked by TommyBean M to Helen on 13 Nov 2014.
    • Photo: Helen Johnson

      Helen Johnson answered on 13 Nov 2014:

      Hi Tommy. We know that galaxies looked very different in the early Universe than they do today. They had lots more gas and were forming stars at incredibly high rates. There was also much more activity caused by matter falling onto black holes at the centre of these galaxies.
      As we look back in time we also see what we call a ‘hierarchical growth’ of structure – small things coming together to form larger things. Galaxies begin to form groups of galaxies, and groups become part of large clusters of galaxies. All of this structure is traced by dark matter, which makes up about 75% of all matter, yet we can’t see it.

Comments