The Eagle Nebula (M16) is visible through any size telescope, but only large ones will let you see the Pillars of Creation. Credit: R. Jay Gabany
Serpens the Serpent is unique among the constellations because it’s separated into two parts, with Ophiuchus the Serpent-bearer between them. Serpens Caput (the head of the serpent) lies to the west of Ophiuchus, and Serpens Cauda (the tail of the serpent) lies to the east.
Serpens Caput is the larger of the two, taking up roughly 67 percent of the area. Together, they comprise the 23rd-largest constellation, which takes up about 1½ percent of the sky. But size doesn’t equal brightness; of the 88 constellations, Serpens ranks 67th in that category. It lies opposite the Sun on June 6, so the two months before and after that date are the best times to view it.
