You don’t often see images of this month’s “Image of the Month” and I’m really not quite sure why this is. The mini-coathanger cluster is a small asterism lying in the constellation Ursa Minor, so it can be imaged all year round, not just in May 🙂 However, as Ursa Major is very well placed this month and Ursa Minor is just next door – I chose May to image the mini-coathanger. As its name suggests, this is a small version of the much more famous Coathanger cluster in the constellation Vulpecula (which was a New Forest Observatory APOD a while back). A very pretty little asterism, and if you look very closely you will see that one of the “stars” that makes up the mini-coathanger is in fact a galaxy, which just makes the object even more interesting IMO. As this is a star image we don’t need to go for particularly long subs and 5-minutes at f#4.5 with a 90mm refractor is plenty. If you can get 4-hours or more total imaging time on this object then you should end up with a very nice image of an asterism that doesn’t seem to get very much attention. Plenty of stars nearby that are bright enough for the autoguider if you don’t actually use one of the mini-coathanger stars.
Well, the nights are getting considerably shorter and we are about to enter my “dead season” as far as deep-sky imaging is concerned, so make the most of these May nights as it is the last time in quite a while before we can return to some decent imaging conditions.
Until next month – happy imaging!!