Summer observing can be challenging for northerner’s for various reasons, some of which include the lateness of astronomical darkness, heat and humidity, plus the profusion of biting insects that enjoy feasting upon our exposed skin. However, the beauty of the summer Milky Way arcing over our heads is often enough of a draw for folks to step outside despite the things that make it uncomfortable. Of course for those folks far enough north, it is unfortunately a time when full on astronomical darkness simply does not occur, causing them to take a hiatus from deep sky observing. Folks down south on the other hand have more darkness, but depending upon location may have to deal with weather issues and cloudiness. For sure there is always something waiting to rob us of our precious clear skies from time to time, plus the ever unpopular light pollution!
Anyway, let’s get on with the observing project I have for you during the months of July and August. I hope you enjoy pursuing these objects and as always, please share your experiences with us. We can all gain insight from one another’s experiences, as we pursue this most amazing pastime.
Northern Celestial Hemisphere
The little arrow constellation, Sagitta, is not one that is typically thought of as a deep sky treasure trove. Its main claim to fame is the fact that it lies directly within the main plain of the visual Milky Way band, and that it contains one
We will focus here on its one
Initially it may be difficult discern within the rich star field, but pay close attention as it does present a rounded glowing knot of light against the backdrop of the Milky Way. It responds well to
Though the constellation Lyra is almost always equated with the amazing planetary nebula, M57, also known as the “Ring Nebula”, it is also home to numerous open clusters and a host of modestly bright to very dim galaxies. But one treat to be found there is this globular cluster. Charles
This cluster can be found about 4.5° southeast of mag 3.2 Gamma Lyrae (Sulafat) near the Cygnus border. In medium apertures (8 to 12 inch), this nice cluster can appear very grainy in texture, as if near some level of stellar resolution. There may be a few stars resolved across its face even at this
I find this globular a bit of an unsung hero among its object class. It is overshadowed by the nearby planetary nebula M57, and though it sits in a rich stellar field, it doesn’t get as much attention as it deserves. So I hope it will pique your interest beyond simply completing your
This small and fairly dim globular will challenge you a bit I suspect. Discovered in 1845 by John Hind, this is no showpiece by any stretch of the imagination. In medium apertures (8 to 12), one should see it as a small and round diffuse patch of light in a rich stellar field. As
This object is located just over 4° southwest of mag 3.4 Delta Aquilae, where it forms a large (over 1° in extent) triangle with 21 Aquilae (mag 5.1) and 23 Aquilae (mag 5.2). The cluster holds down the southwestern corner of this pattern. Give this one a try, and don’t be afraid to push up the magnification a bit conditions permitting of course.
Southern Celestial Hemisphere
Sagittarius is of course stuffed full of globular clusters. One could throw a dart at a chart of the famed archer and stand a reasonable chance of hitting a globular! (smiley) It would be easy to spend a few evenings in this constellation chasing them and nothing else. Here we focus on this beautiful cluster that sits just north of the Sagittarius-Corona Australis border. This is a beautifully bright cluster that is readily apparent within its field. It will exhibit noticeable density and brightness within its central region, set within a thinner and sparse outer halo. Some modest resolution is certainly possible at medium
This beauty was discovered by James Dunlop in 1826 during his survey of the southern sky from Parramatta, New South Wales, His time spent in Australia was the first real deep telescopic study of the southern skies. It was an important precursor to the more extensive southern sky survey conducted by John Herschel from the Cape Territory in southern Africa by John Herschel, from January 1834 to February 1838. For this endeavor, Herschel dismantled and moved his father’s famous 18.7 inch reflector to conduct his search of the southern skies.
I admit this is one of my favorite globular clusters. Not because it is showy or resolves deeply however. Rather I find its close proximity to the magnitude 3.2 star HD 161892 (sometimes listed as G Scorpii) to provide a beautiful visual contrast that is intriguing in the eyepiece. The star HD 161892 and
An interesting aside to this is that both Dunlop and Herschel mention the star just west of the cluster in their notes as Gamma Telescopii. That is because this star was once in Telescopium as it was originally plotted. However, in time the constellation borders were redrawn and the star that was once Gamma Telescopii then located in Scorpius and renamed G (Bayer designation) Scorpii.
This tight little ball of stars stands out next to the bright star G Scorpii in the eyepiece, though it is obviously not as bright overall. However, the aspect of it being a fuzzy little orb as opposed to a single stellar point draws one’s attention its way. One may pick up hints of the cluster’s presence even in a magnified optical finder scope under darker skies. Even small scopes will definitely tell you that this is not a pair of stars, but rather a star and a fuzzy knot of light. As one increases
We now return to Sagittarius to wrap up our targets for this edition. This globular is certainly not one of the brightest of its object type, and will be challenging for some. This cluster is significantly obscured by foreground dust within our galaxy, and thus its true brightness is reduced from our vantage point. Found in the northwestern quadrant of Sagittarius in a star rich field, it lies nearly 2.5° southwest of the open cluster
In medium apertures (8 to 12 inch), one should notice its central region which gradually brightens to a noticeable core. However, any level of resolution will not likely be seen. In larger apertures one may begin to see a mottled or grainy texture, hinting at resolution being just out of reach.
While you have this object in the eyepiece, do look for a another
So there it is. You have the targets, you have the equipment and it is now up to you to find the desire and motivation to pursue! I encourage all to get out there and give these a try, even if you've seen them before. It never hurts to take a fresh look at something you've seen before. Why? Well you just never know, with a little closer study you just might notice something different this time around. Good luck and most importantly, have fun my friends.
I don’t usually include Ngc6760 in Aquila on my observing list but I noted during a session last September that it was a small, sparse and fairly dim glob. I’ll have to give it another try soon I hope! Objects in my southern sky have to rise to at least 20 degrees to clear my southern observatory wall and 
