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Light in intergalctic space/ voids

  1. Aug 1, 2011 #1
    Here on Earth the furthest object that can be seen with the naked eye is the Andromeda Galaxy at aprx. 2 million light years. And even that is not very easy to see.Obviously it is harder to see here on Earth in our light polluted skies and it would be easier to see in space. But even that difference I would think has to have some to limit. So my qestion is, if you were in intergalactic space say in a large void between galaxies in a galactic cluster or in a really large void between galactic clusters and you were floating along in a space suite, would you even be able to see any light at all ,Or would you find yourself floating in a seemingly pitch black endless void? Or, are our eyes sensitive enough that you could percieve galaxies or clusters of them as at least a blur of light from any distance.
    Last edited: Aug 1, 2011
  2. jcsd
  3. Aug 2, 2011 #2
    In deep intergalactic space. You can't see even a glimmer of light even from a supernova, with your eyes. Its pure blackness. Its the nature and majority of the universe. Pure blackness.
  4. Aug 2, 2011 #3


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    When you say in space and you suggest that this has to have a limit what do you mean? Light pollution only occurs because we have an atmosphere.

    I'm not entirely sure how to work it out for an eye but there was a few threads I partook in a while ago that looked at how big a telescope would have to be to detect objects of specific sizes.


    Er...what? "Pure blackness" doesn't make much sense at all. Space doesn't absorb light like a dark fog. What do you mean by "deep" intergalactic space?
  5. Aug 2, 2011 #4


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    The most distant object observable from earth with the naked eye was GRB 080319B, magnitude 5.8, in 2008. It was 7.5 billion light years from earth.
    [re: http://www.nasa.gov/mission_pages/swift/bursts/brightest_grb.html] [Broken] The faintest object visible to the naked eye is about magnitude 8 [http://web.me.com/mdiastro/faintestobject/Welcome.html], so, GRB 080319B would have been visible from anywhere within the observable universe.
    Last edited by a moderator: May 5, 2017
  6. Aug 2, 2011 #5
    well I've looked and lokked and andromeda is HARD to see !! and this a GALAXY only 2 million light years away.. and it is listed as the most distant object you can see with the naked eye...so if your in a void that 20, 30, 40, 50 million light years away from the closest stars er galaxies ,than that light would have to be so faint I dont see how you could possibly see anything with your naked eyes...and I'm just going on how dim a huge freaking galaxy is to us from only 2 Mil light years away...and what the dude said about "deep intergalactic space" I think he means the sme thing I was refering to..the HUGE empty voids between Galactic clusters. If we can BARELY see our closest neighbor ANDROMEDA at 2 mil light years. Just imagine floating along in a space suit in between our galactic cluster.......



    " Beyond Our Local Group Many more than a few dozen galaxies reside in the Universe. Time exposures made with large telescopes, such as that in Figure 2.2, reveal thousands of galaxies within virtually any small field of view. In all, astronomers estimate that ~40 billion other galaxies inhabit the observable Universe. And virtually all of them are much farther away than even the distant members of our local galaxy cluster. For millions of light-years beyond the edge of the Local Group, there appears to be nothing—no galaxies, no stars, no gas or dust—just empty intergalactic space."

    "STRIVE TO APRECIATE the far recesses of deep space outside the Local Group. Searching a seemingly interminable void, we occasionally sight a “field” galaxy scattered lonely here and there. Not until we reach a distance of ~60 million light-years away do we find another galaxy cluster, an unmistakable volume of space brimming with galaxies. This cluster is especially rich, containing not just ~35 galaxies like in our own Local Group; the so-called Virgo Cluster harbors nearly 3,000 galaxies. Try to visualize in mind’s eye thousands of individual galaxies all clustered in a swarm, each one housing about a 100 billion stars. No wonder most people have trouble appreciating the immensity of matter, space, and time in the Universe. Astrophysicists are no different; we, too, share the burden of trying to fathom such humongous sizes and scales, including astronomical numbers of astronomical objects." (they have to use BIG telescopes and time exposures to see the other clusters out there)
    And 60 MILLION light years away!!! from our local group., to the next cluster.there is not gonna be too much visible light(to the naked eye") ok a gamma ray burst once in a while might cause you to see a little flash once in a while ! and I dont know how far but the next closest one (cluster) is surely double that... Do you follow what I'm trying to say?? or IMAGINE??... floating in a space suit in empty space 30 million light years ( the middle of the void) from the closest..light..anything.Pitch *** black. talk about a sensory deprivation situation....the universe is really really BIG!? and dark thats all i am trying to say, figure out..imagine

    Last edited: Aug 2, 2011
  7. Aug 3, 2011 #6


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    Yes, the universe is big. You'll probably find that a lot of the members here really appreciate that as they work in the field. The biggest difference between here and intergalactic space is light pollution that makes a hell of a difference. I live in London, at night I'll be lucky to see more than 6 stars.
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