• IrateAnteater@sh.itjust.works
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    13 hours 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.

    • wewbull@feddit.uk
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      2 hours ago

      Right, but I don’t get why this thread is full of people talking about collisions. Even if it was moving at the speed of light (it’s not) it’s still billions of years away.

      It would just prove our theory of universe inflation to be incorrect.

    • OrganicMustard@lemmy.world
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      11 hours 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.

      • Cethin@lemmy.zip
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        5 hours ago

        I was going to argue with this too, but the meme says blueshifting, not blueshifted. They’re right, but mostly because the meme is probably written poorly. Maybe they meant it’s accelerating toward us though. Idk.

    • yaroto98@lemmy.world
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      12 hours 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.