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How many of the luminous dots that we see naked are galaxies and not stars from our galaxy?

I imagine that the majority of the luminous points that we see naked eye during the night, are actually stars from our galaxy. But how many of them are other objects (other galaxies, nebula, etc.), excluding planets from our Solar System?

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  • $\begingroup$ Ok, Il'll try there. I thought it was inactive, since it is beta and has only 317 questions. I also read on area51 that the previous astronomy Q&A site had been closed and that astronomy questions had been merged into this site. $\endgroup$
    – Mario Stefanutti
    Nov 26, 2013 at 15:06
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    $\begingroup$ By the way, for clarity's sake, we are not an inactive site per se. We have slowed down substantially, but we are in that developmental phase that many beta sites experience where the initial activity has slowed and we are in need of people like you to come and ask great questions! $\endgroup$
    – called2voyage
    Nov 26, 2013 at 16:47
  • $\begingroup$ Wow. The answer came at the speed of light. Sorry for having considered this site inactive. Thanks! $\endgroup$ Nov 26, 2013 at 17:12

2 Answers 2

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In the best sky conditions, the naked eye (with effort) can see objects with an apparent magnitude of 8.0. This reveals about 43,197 objects in the sky.

There are 9 galaxies visible to the naked eye that you might see when observing the sky, and there are about 13 nebulae that you might see.

Sources:

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    $\begingroup$ Under typical dark sky conditions, the limit is about 6.0. 8.0 would require extraordinary conditions (and much better eyes than mine). The only galaxies visible to the naked eye in normal conditions (outside our own) are the Large and Small Magellanic Clouds, M31 (Andromeda), and M33 (Triangulum). There are only sporadic reports of other galaxies being seen by the naked eye. (There's some argument that Omega Centauri is a galaxy rather than a globular cluster.) Reference: en.wikipedia.org/wiki/Naked_eye#Naked_eye_in_astronomy $\endgroup$ Nov 27, 2013 at 16:24
  • $\begingroup$ @KeithThompson Right, there's more on that in my linked sources. The OP asked "how many" which is a question which often looks for the maximum extent. So I answered with the most possible that could be viewed. $\endgroup$
    – called2voyage
    Nov 27, 2013 at 17:30
  • $\begingroup$ I would like to add the obvious that most of the stars we see are bright luminous stars and in no way represents the majority of stars in the galaxy or even the nearby solar neighborhood. $\endgroup$ Jun 8, 2017 at 0:34
  • $\begingroup$ Thoughts on including an estimated star count, as well? See Sky & Telescope, Earth Sky, and UBC Astronomy Club for details. $\endgroup$ Oct 21, 2019 at 23:46
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    $\begingroup$ @InjamulMohammadMollah re "...in case anyone visits" one of the nice side effects of edits is that they bump a question back into the active queue, so folks will definitely now visit. Welcome to Astronomy SE! $\endgroup$
    – uhoh
    Nov 22, 2020 at 21:34
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On a visit to Yosemite in May of 1975 or 1976, I saw a very clear, very dark and moonless night sky that was studded with stars. I gazed at the sky for a long time because it was so beautiful, and in that sky I also saw galaxies. I don't remember exactly how many galaxies, but there were multiple galaxies. As I gazed at it, I thought to myself that I would probably never again see such a sky (I was right) and that for the rest of my life I would doubt that I had seen such a sky (I was right). I kept gazing at it, to fix it as much as possible in my memory. Still, the memory is elusive. My sense is that there might have been twenty or more galaxies in that sky. Would twenty or more galaxies visible to the unaided eye have been possible forty-five years ago? Elevation about 3500 feet, clear dark night, 1975-6.

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    $\begingroup$ Actually, elevation can be a disadvantage, though 3500 feet is probably ok. The reason is that diminished oxygen results in poorer visual acuity. In fact 3500 feet is probably ideal because you are above any surface dust layer but not so high that there is much of a decrease in oxygen. $\endgroup$
    – ProfRob
    Dec 16, 2020 at 13:50
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    $\begingroup$ I'm sorry to tell you that you probably did not see any galaxies at all. There are only a few that can ever be seen with the naked eye. The two easiest (the Magellanic clouds) can never be seen from Yosemite's latitude, and the next two (M31 & M33) aren't up that time of year. Any others are extremely dim. I suspect you probably saw a number of open clusters or other groupings of stars, not galaxies. $\endgroup$
    – D. Halsey
    Dec 16, 2020 at 23:30

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