Sagittarius (♐, and Latin for Archer) is a constellation of the zodiac, commonly depicted as a centaur drawing a bow. Sagittarius lies between Scorpius to the west and Capricornus to the east. Its brighter stars form an easily recognizable teapot shape.
The name Sagittarius has also been given to a recently discovered galaxy, the Sagittarius Dwarf Elliptical Galaxy, located just outside the Milky Way.
Notable features
The constellation is easily recognizable through an asterism called the Teapot. The stars Kaus Media (δ), Kaus Australis (ε), Ascella (ζ), and φ Sagitarii form the body of the pot; Kaus Borealis (λ) is the point of the lid; Alnasl (γ) is the tip of the spout; and Nunki (σ) and τ Sagitarii the handle. [1] [2]
The α star, Rukbat , is nowhere near the brightest star of the constellation, having a magnitude of only 4.0.
Notable deep-sky objects
The Milky Way is at its densest as it passes through Sagittarius, as this is where the galactic center lies. Consequently, Sagittarius contains many star clusters and nebulae. One of the brightest of the star clusters is M55, about 7.5° west of δ Sgr.
The constellation contains nebulae such as the Lagoon Nebula (M8), near λ Sagitarii, beautiful in telescopes; the Omega, Swan, or Horseshoe Nebula (M17), near the border with Scutum; and the Trifid Nebula (M20), a large nebula containing some very young, hot stars.
The complex radio source Sagittarius A associated with the galactic centre is also here. Astronomers believe that Sagittarius A may contain a supermassive black hole.
Mythology
Sagittarius has the rough appearance of a stick-figure archer drawing its bow, and when including the fainter stars, appears to have a horse-like body [3]. The greeks identified such a figure as a centaur, wheras earlier cultures, such as the Babylonians, identified it as the god Pabilsag (which also had wings and a lion's head).
In Greek mythology, Sagittarius was sometimes identified as Chiron, aiming his bow at the Scorpion, although the more usual identification of Chiron was with the constellation Centaurus. The constellation Sagitta was sometimes considered to be an arrow fired by Sagittarius.
Other early identifications include that of a rattle, which the constellation's brightest stars considered together vaguely resemble. As such, together with other constellations in the Zodiac sign of Sagittarius (specifically, Cygnus, Lyra, and Aquila), may be a significant part of the origin of the myth of the Stymphalian Birds, one of The Twelve Labours of Herakles.
Astrology
The astrological sign Sagittarius (November 22 - December 21) is associated with the constellation. In some cosmologies, Sagittarius is associated with the classical element Fire, and thus called a Fire Sign (with Aries and Leo). It is also one of the four Mutable signs (along with Gemini, Virgo, and Pisces). Its polar opposite is Gemini. Each astrological sign is assigned a part of the body, viewed as the seat of its power, Sagittarius assigned with the hips and thighs. Its ruling planet is Jupiter. The symbol for Sagittarius is the centaur or archer.
See Also
