Ophiuchus, the Serpent Bearer, is one of the 88 modern constellations. Its name, derived from ancient Greek, translates to “serpent-bearer,” depicting a man grasping a snake. This large, sprawling star pattern straddles the celestial equator, making it accessible to observers across almost the entire globe. Understanding its seasonal position helps stargazers know when and how to locate this significant star field.
Defining the Serpent Bearer
Ophiuchus is the 11th largest constellation, covering 948 square degrees. Its mythological origin is linked to Asclepius, the Greek god of medicine, who was honored by Zeus and placed in the heavens. The serpent is represented by the constellation Serpens, which Ophiuchus divides into Serpens Caput (Head) and Serpens Cauda (Tail). The constellation’s brightest star is Rasalhague (Alpha Ophiuchi), a white giant star whose name means “the head of the serpent collector.”
Seasonal Visibility and Optimal Viewing
Ophiuchus is best viewed during the Northern Hemisphere summer and early autumn, with peak visibility occurring in July. During this time, the constellation reaches its highest point in the sky, or culmination, around 9:00 p.m. local time. Northern Hemisphere observers can generally spot Ophiuchus in the evening sky from May through October. Southern Hemisphere observers find the constellation highest overhead during their winter months.
The constellation’s location on the celestial equator means it is visible from almost every inhabited part of the Earth, between latitudes of +80° and −80°. Although visible for much of the year, the sun passes through its boundaries from late November to mid-December, rendering it invisible. For the best viewing experience, observers should target the dark hours around midnight during the peak summer months.
Locating Ophiuchus in the Night Sky
Star-hopping is the primary method used to find Ophiuchus. The constellation is situated between Scorpius to the southwest and Hercules to the north. Its brightest star, Rasalhague, marks the head of Ophiuchus and is located near the head of Hercules. The southern part of Ophiuchus borders Sagittarius and sits north of the reddish star Antares, the heart of Scorpius.
The constellation’s main body appears as a large, irregular pentagon, with Rasalhague forming the apex. This area is dense with deep-sky objects because it lies close to the central plane of the Milky Way galaxy. Within its boundaries are seven Messier objects, all of which are globular star clusters like M10 and M12.
The Thirteenth Constellation
Ophiuchus is often discussed due to its status as a 13th constellation of the Zodiac. The ecliptic, the Sun’s apparent path, passes directly through Ophiuchus, and the Sun spends approximately 18 days within its boundaries (November 30 to December 18). The traditional 12-sign astrological zodiac is based on an ancient Babylonian system that divided the ecliptic into 12 equal segments. This system does not correspond to the modern, unequal-sized constellations. Therefore, Ophiuchus is an astronomical member of the zodiacal constellations but is not recognized within the 12-sign framework of Western astrology.