• atomicbocks@sh.itjust.works
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    4 days ago

    You can’t see millions of light years without a telescope. If you could the night sky would be white not black. Or more likely a weird shade of red.

    • trem@lemmy.blahaj.zone
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      3 days ago

      Why you can’t see distant stars:

      • The light fans out the further it travels, because the angles just drift further apart.
      • The higher the distance, the higher is the chance of something else getting in the way. In particular, clouds of gas or dust can dim the star without blocking it completely.

      I guess, the following isn’t technically relevant here, but:

      • The space in the universe expands for unknown reasons. When light travels larger distances through this expanding space, its wavelength is stretched as well. This causes the light color to shift towards red, then infrared, then microwave radiation. We can’t see the latter two anymore, so they appear dark.

      I assume, it’s not relevant here, because otherwise the stars would appear red. Although, I don’t know, if maybe Rayleigh Scattering counteracts that?

      But yeah, there’s a similar paradox where this redshift actually becomes relevant: https://en.wikipedia.org/wiki/Olbers’_paradox

      • mkwt@lemmy.world
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        3 days ago

        I assume, it’s not relevant here, because otherwise the stars would appear red.

        Correct. The stars you can see with your eye are mostly all too close by to have a strong red shift.