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20. M11, Wild Duck Open Cluster
Notes: M11 is only 1/3 the distance to M13 (19). The distance is only 1/4 to 1/5 the radius of the Galaxy. It appears that clusters are scattered about the Milky Way like raisons in a pudding. We (imagers) don't know if they are mostly contained within the spiral arms and/or core or are also found in the halo. We don't know if the open clusters have the same distribution as the globular clusters. According to Wikipedia, M11 has some 2900 stars and an estimated age of 220 million years. Compare the globular cluster M13, which has a mass of 600,000 Suns and an estimated age of 11.65 billion years. While both are clusters, M11 and M13 are very different kinds of deep sky objects. The difference in age suggests that the search for alien life and mineral wealth would have better prospects on M11, and it would be easier to reach. With lightspeed transport, we could be there in only 22,000 years. But M11 has relatively few stars, so that reduces the chances of finding alien life.
We did several iterations of polar alignment and checked for DEC drift by slewing to Mizar and watching it on the fine grid in PHD with capturing on, but guiding off. There was a barely perceptible drift north and south over 6 minutes of a distance less than 1/3 the radius of Mizar. At the end of that time, the Mizar appeared not to have drifted. The stars in this image appear to be nearly round. We later slewed to M27 and got stars that showed a bit of drift. Zoom in/out with ⌘↑(+/-) (Mac), ctrl (+/-) (PC).