Previously, I had never imaged M12, having subscribed, as many do, to the belief that "if you have seen one (or a few) globular clusters, you have seen them all." As I have matured as an astrophotographer, however, I have come to appreciate that this belief is patently false. Close inspection of decent images of globs reveals that there are (sometimes admittedly subtle) differences among the clusters. When I was searching the internet for published images of M12 in preparation for shooting this target myself, I was immediately struck by some of this target's individuating characteristics. Most obvious is the fact that it is more elliptically than circularly shaped. My eye was also caught by what appears to be at least two background galaxies at the five o'clock position on the periphery of the cluster. I found identifying information for only one of these galaxies on the SIMBAD website. The galaxy is 2MASX J16470200-0202314, located some 827 million light years from us.
M12 itself is located about 23,000 light years from earth. As globs go, it is relatively diffuse (though nowhere near as diffuse as
NGC 5466, which I imaged last month). It has been recently found to have an unexpectedly small population of low-mass stars. The discoverers of this fact hypothesize that M12 lost about a million stars of this type as it passed through the plane of the Milky Way in its orbit around the galactic center.
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