Andromeda and the Moon (no photos)

....Dawes limit states that the hubble can only resolve at .049 arc seconds. So, no atmospheric turbulence to worry about, no adaptive software required. What this really means is that we can't resolve stars that are closer than .05 arc seconds to another star.

If the stars in Andromeda away from the galactic center were spaced 4 LY apart in the plane of the image, then that would take care of the .049 arc seconds I suppose. But then there would be a lot of 'layers' in that image due to the galactic thickness, which I'd think would turn those points of light into a smeary soup.
 
Not sure I follow what you mean by layers?
The photo that NASA shows of Andromeda's "individual" stars isn't one layer of stars deep (i.e. a more-or-less flat plane) - the thickness of the galaxy in that photo is probably at least a few hundred light years. Since we aren't going to see the bodies of those stars, as they are more than a million times too small, and we see only points of light that are built on a long time exposure, it seems to me that the myriad number of stars underneath the closest stars in the photograph would smear the points of light to the point that the light from individual stars couldn't possibly be seen. In our position in the milky way the average distance to neighbor stars is less than 4 LY, which is probably about the same in the Andromeda photo (far away from the center of the galaxy). That's a lower-resolution limit at Andromeda's distance, but within each 4 LY space, there are not only the closest stars, but lots more behind them and to the side that would smear their light.
 
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