• IrateAnteater@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    34
    ·
    3 months ago

    If something is red shifting, it’s accelerating away from you. If something is blue shifting, it’s accelerating towards you. An entire galaxy accelerating towards you is somewhat concerning.

    • OrganicMustard@lemmy.world
      link
      fedilink
      English
      arrow-up
      14
      ·
      3 months ago

      Redshift comes from relative velocity (and other effects), not acceleration. Andromeda’s light is blueshifted as it’s moving towards us, but it’s not accelerating.

    • yaroto98@lemmy.world
      link
      fedilink
      English
      arrow-up
      11
      ·
      3 months ago

      On top of that, we’ve found that basically everything is redshifting as the universe expands. So to see a blueshifting galaxy would mean something potentially unnatural.