Serpens is unique among modern constellations in that it is separated into two parts. Serpens Caput, the head, begins near Corona Borealis, and descends southward until it connects to Ophiuchus (the serpent bearer). Serpens Cauda, the tail, begins on the other side of Ophiuchus and ascends north and eastward, terminating near Aquila. Serpens is often depicted as passing behind Ophiuchus and emerging from the other side. Since Serpens is a lengthy constellation that extends primarily in an east-west direction, it reaches its highest nightfall ascension beginning in June with the head and ending with the tail in August. The entire constellation is situated for best nightfall viewing in July.
Serpens Cauda extends into the Milky Way, so there are several deep sky objects in that section. Two of these are Messier objects, M5, and M16 (the Eagle Nebula, which includes the Pillars of Creation and its associated star cluster). Hoag’s Object is a face-on example of a very rare class of galaxies known as ring galaxy. http://en.wikipedia.org/wiki/Serpens
Hercules is one of the 88 modern constellations that are among the 48 constellations cataloged by 2nd century astronomer Ptolemy. It is named after the Roman mythological hero adapted from the Greek hero Heracles. It is a northern constellation that lies just off of the Summer Triangle, and near Ophiuchus. Hercules reaches its highest nightfall ascension in July. A squarish asterism called the Keystone is likely to catch the eye first when looking in this area. Older visualizations of this constellation depict the Keystone as Hercules’ hips, while some more modern visualizations depict the Keystone as Hercules’ head.
One of the most notable Messier objects, the Hercules Cluster (M13), is a bright globular star cluster that can be seen with the naked eye in dark skies. It is located between the two stars comprising the Keystone’s western edge. M92 is the only other Messier object in this constellation. The largest and most massive known structure in the universe, The Hercules-Corona Borealis Great Wall, is a filament of galaxies that is situated on Hercules’ border with Corona Borealis. http://en.wikipedia.org/wiki/Hercules_(constellation)
Corona Borealis is one of the smallest, but prettiest constellations. It is located between Boötes and Hercules, and is best seen when it reaches its highest nightfall ascension in September. It is also one of the 48 constellations cataloged by 2nd century astronomer Ptolemy. This constellation’s name is inspired by its shape: its main stars form a semicircular arc with Alphecca, a bright jewel, situated about half way around the arc. This distinct constellation easily catches the observers eye in a dark sky, but often escapes notice in a light-polluted urban sky. http://en.wikipedia.org/wiki/Corona_Borealis