Also note there are several distant galaxies visible through the disk of M31. The most obvious below NGC 206 and very slightly to the right. Other fuzz balls can be seen in the image that are also likely galaxies as they are not listed among the star clusters of M31. Nor does NED pick them up at all. Also there are other very blue star clouds to be seen as you scan around the image. Most toward the far right of my image. I processed the image to suppress the background galaxy to emphasize the stars in the galaxy itself. This caused the fainter parts of the galaxy to vanish nearly completely long before the true edge is reached. It feels rather odd to be scanning an image 4008 pixels across and stay within a small region of M31. When I got into DSO imaging 57 years ago now (1956) I never dreamed I'd ever take an image at this image scale. I was happy to see NGC 206 as an unresolved blob in M31.
One thing I learned is that NGC206 is home to several Cepheid and eclipsing binary stars. The DIRECT Project http://www.astronomy...nek/CfA/DIRECT/ has used these stars to determine the distance to the star cloud and a lot more in the galaxy and thus M31. I found nothing at the site saying what distance they found. APOD says they found a distance of 3 million light-years http://apod.nasa.gov...d/ap990402.html which is further than most estimates I've seen. Original Hipparcos data said 2.7 million light-years which seemed to get reduced to 2.5 million or increased to 2.9 million light-years for reasons I never did discover. Now this figure of 3 million light-years caught me by surprise. If right maybe we have another billion years before we collide with it.
14" LX200R @ f/10, L=8x10'x1 RGB=2x10x2, STL-11000XM, Paramount ME
Full image at 0.5" per pixel rather than my normal reduced 1" per pixel image (4008x2672 pixels and 2.75 megabytes)
My normal 1" per pixel image scale