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Naked eye view from intergalactic space

  1. Apr 9, 2012 #1
    If one were located in intergalactic space, say halfway between the Milky Way and Andromeda, what would space look like to the naked eye?

    Would we see a relatively small number of galaxies and otherwise mostly just darkness? From that position would the Milky Way and Andromeda have any semblance of their spiral shapes to us (again to the naked eye), or would they appear like stars or perhaps nebulae at best?

    Just trying to visualize -- thanks for any insights.

  2. jcsd
  3. Apr 9, 2012 #2

    Jonathan Scott

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    You know what the Andromeda galaxy looks like to the naked eye from here? In my experience it's a small fuzzy nebulous blob, which appears a bit more extended if the sky is very dark.

    I'd guess that if you were half way there, it would basically be a fuzzy blob of twice the angular diameter, and looking back the Milky Way would be similar. I don't think much else would be visible at all; perhaps one or two satellite galaxies.
  4. Apr 9, 2012 #3


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    Frankiewicz, Welcome to Physics Forums!

    I agree with Jonathan Scott's description of what you would see. This brings to mind “The Cosmological Principle” which we expect would apply everywhere in the universe.

    “The cosmological principle is usually stated formally as 'Viewed on a sufficiently large scale, the properties of the Universe are the same for all observers.' This amounts to the strongly philosophical statement that the part of the Universe which we can see is a fair sample, and that the same physical laws apply throughout. In essence, this in a sense says that the Universe is knowable and is playing fair with scientists.”

  5. Apr 9, 2012 #4
    If you had good eyesight you'd probably be able to make out a couple other nearby galaxies, given the lack of ambient lighting. M81 and M82 are the first ones that come to mind, since with a good trained eye, one can make apparently make them out with a good knowledge of the sky and perfect viewing conditions.

    So, it would be mostly black.

    And @ Bobbywhy

    Wouldn't it be a cruel joke by existence if our laws of physics were local and changed slightly throughout the universe and ~that~ was the reason we've not been contacted by extra terrestrials?
  6. Apr 14, 2012 #5


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    At half the distance, the apparent size of Andromeda would be 4x larger than from earth.
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