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There are stars here, there, and "everywhere" - but are there places in space that are so far from stars that no light reaches?

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    $\begingroup$ Do you mean no light visible to the unassisted human eye, or really no light at all. $\endgroup$ – Steve Linton May 12 '19 at 21:53
  • $\begingroup$ Same question on Physics.SE: physics.stackexchange.com/q/390742/200019 See also physics.stackexchange.com/q/473330/200019 $\endgroup$ – DrSheldon May 12 '19 at 22:35
  • $\begingroup$ If "light" includes infra-red, then there is light even inside a hollow sphere. $\endgroup$ – hdhondt May 12 '19 at 23:48
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    $\begingroup$ If "space" means anywhere in the universe, and "light" means visible light, then the back of my bedroom closet with the door shut would be a legitimate answer. It's really not clear exactly what the question is looking for. $\endgroup$ – Ray Butterworth May 13 '19 at 0:40
  • $\begingroup$ @RayButterworth Or "a couple inches underground". :-p $\endgroup$ – ceejayoz May 13 '19 at 1:34
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Asking for no light at all is a stretch. But an important component within our Solar System is where no sunlight reaches. Crater bottoms at the Moon's North Pole have a confirmed presence of water ice, permanently shadowed from the sunlight that would otherwise vaporize it.

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  • $\begingroup$ Wikipedia sez that the sky needs to be darker than about +20 magnitude per square arcsecond for the Milky Way to be present, which means that the brighter areas are about +2.4 magnitude per square degree. However, the bright areas of the milky way may not be visible from north pole crater-bottoms, so it's going to be pretty darn dark there. $\endgroup$ – uhoh May 14 '19 at 4:47
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The Boötes void is 330 million light years in diameter and is known to contain only 60 galaxies. If these were evenly distributed across the centre of the void (which they are not) they would be 5.5 million light years apart. Being distributed through the void the spacing would be very much greater. So there are places where there are no galaxies for ten million light years or more. https://en.wikipedia.org/wiki/Bo%C3%B6tes_void

The Triangulum galaxy is 3 million light years from Earth and is on the very edge of what can be seen with the naked eye. https://en.wikipedia.org/wiki/Triangulum_Galaxy

Therefore there must be many places in the Boötes void where no galaxies can be seen with the naked eye. However some galaxies would become visible with a medium sized telescope if you knew where to look.

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