SAGITTARIUS

Sagittarius, one of the constellations of the zodiac, graces the Southern celestial hemisphere. It stands as one of the 48 constellations documented by the 2nd-century astronomer Ptolemy and endures as one of the 88 modern constellations. This constellation is symbolized by the archer, depicted as a centaur drawing a bow. Positioned between Scorpius and Ophiuchus in the west and Capricornus and Microscopium in the east, Sagittarius’ Latin name translates to “archer.” Notably, the westernmost part of Sagittarius holds the center of the Milky Way, home to Sagittarius A.

Mythology

In Babylonian lore, Sagittarius was linked to the god Nergal, portrayed as a centaur-like being drawing a bow and releasing an arrow. This depiction typically featured wings, two heads—one resembling a panther and the other human—and a scorpion’s stinger arched over its more traditional horse’s tail. The Sumerian moniker Pabilsag comprises two components: “Pabil,” signifying ‘elder paternal kinsman,’ and “Sag,” denoting ‘chief’ or ‘head.’ Consequently, the name can be interpreted as the ‘Forefather’ or ‘Chief Ancestor.’ This ancient figure bears a resemblance to modern representations of Sagittarius.

Greek mythology

In Greek mythology, Sagittarius is typically associated with a centaur—a creature that’s half human and half horse. However, this identity has led to some ambiguity, possibly stemming from the Greeks’ incorporation of the Sumerian constellation. Some attribute Sagittarius to the centaur Chiron, who was the offspring of Philyra and Cronus. Chiron was known for transforming himself into a horse to evade his jealous wife, Rhea, and for his role as Jason’s tutor. Since there are two centaur constellations in the sky, some link Chiron with the other, named Centaurus. Alternatively, an alternate tradition suggests that Chiron devised the constellations Sagittarius and Centaurus to aid the Argonauts in their quest for the Golden Fleece.

Another mythological perspective, advocated by Eratosthenes, identifies the Archer not as a centaur but as the satyr Crotus, who was the son of Pan and credited by Greeks with inventing archery. According to legend, Crotus frequently engaged in horseback hunting and resided among the Muses, who requested that Zeus place him in the heavens, where he’s observed showcasing his archery skills.

Interestingly, the arrow of this constellation points directly toward Antares, known as the “heart of the scorpion.” Sagittarius appears ready to defend Hercules or avenge Scorpius if the latter ever threatens Hercules or seeks retribution for Scorpius’s slaying of Orion.

Terebellum

In the western region of the constellation, Ptolemy also documented the asterism Terebellum, which comprises four 4th magnitude stars. Among them, Omega Sagittarii stands out as the closest and most rapidly moving member.

Astrology

As of 2002, the Sun’s presence in the constellation Sagittarius spans from December 18th to January 18th. In tropical astrology, the Sun is associated with the sign Sagittarius from November 22nd to December 21st, while in sidereal astrology, it extends from December 16th to January 14th.

Notable features

Within the constellation Sagittarius, α Sgr is known as Rukbat, signifying “the archer’s knee,” but despite its alpha designation, it shines with a magnitude of only 3.96. Located toward the bottom center of the map, it is not the brightest star in Sagittarius. Instead, Epsilon Sagittarii (ε Sgr), known as “Kaus Australis” or “the southern part of the bow,” holds that distinction with a magnitude of 1.85, making it about seven times brighter than α Sgr.

The second-brightest star in Sagittarius is Sigma Sagittarii (σ Sgr), known as “Nunki,” shining at a magnitude of 2.08. Nunki is a B2V star located approximately 260 light-years away. Its name, “Nunki,” has Babylonian origins of uncertain meaning, but it is believed to represent the sacred Babylonian city of Eridu on the Euphrates, making it one of the oldest star names still in use today.

Zeta Sagittarii (ζ Sgr), referred to as “Ascella,” has an apparent magnitude of 2.61 and consists of a double star system. Its components have magnitudes of 3.3 and 3.5.

Delta Sagittarii (δ Sgr), known as “Kaus Meridionalis,” is a K2 spectra star with a magnitude of 2.71, located approximately 350 light-years from Earth.

Eta Sagittarii (η Sgr) forms a double star with component magnitudes of 3.18 and 10. On the other hand, Pi Sagittarii (π Sgr), named “Albaldah,” is actually a triple star system with components shining at magnitudes of 3.7, 3.8, and 6.0.

The Bayer designation Beta Sagittarii (β Sgr) is attributed to two star systems: β¹ Sagittarii, with an apparent magnitude of 3.96, and β² Sagittarii, which has a magnitude of 7.4. These two stars are separated by 0.36° in the sky and are located 378 light-years from Earth. Beta Sagittarii, positioned in association with the forelegs of the centaur, goes by the traditional name “Arkab,” signifying the “Achilles tendon.”

Nova Sagittarii 2015 No. 2 was initially spotted on March 15, 2015, by John Seach of Chatsworth Island, NSW, Australia. It is situated near the center of the constellation and reached a peak magnitude of 4.3 before gradually fading.