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Sagittarius

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List of stars in Sagittarius
Abbreviation:	Sgr
Genitive:	Sagittarii
Symbology:	the Archer
Right ascension:	19 h
Declination:	−25°
Area:	867 sq. deg. (15th)
Main stars:	12, 8
Bayer/Flamsteed stars:	67
Stars known to have planets:	10
Bright stars:	7
Nearby stars:	4
Brightest star:	ε Sgr (Kaus Australis) (1.9m)
Nearest star:	Ross 154 (9.68 ly)
Messier objects:	15
Meteor showers:
Bordering constellations:	Aquila Scutum Serpens Cauda Ophiuchus Scorpius Corona Australis Telescopium Indus (corner) Microscopium Capricornus
Visible at latitudes between +55° and −90° Best visible at 21:00 (9 p.m.) during the month of August

Sagittarius (pronounced /ˌsædʒɪˈtɛəriəs//, Latin: archer, symbol , Unicode ♐) is a constellation of the zodiac, commonly depicted as a centaur drawing a bow. Sagittarius lies between Ophiuchus to the west and Capricornus to the east.

Contents 1 Notable features 2 Notable deep-sky objects 3 Mythology 3.1 Astrology 4 See also 5 References 6 External links

The constellation's brighter stars (from left to right on the map: τ, ζ, σ, φ, λ, ε, δ, η and γ² Sagittarii) form an easily recognizable asterism called the Teapot. The Milk Dipper is part of the Teapot. The stars δ Sgr (Kaus Media), ε Sgr (Kaus Australis), ζ Sgr (Ascella), and φ Sgr form the body of the pot; λ Sgr (Kaus Borealis) is the point of the lid; γ² Sgr (Alnasl) is the tip of the spout; and σ Sgr (Nunki) and τ Sgr the handle.^[1][2] The Milky Way can be imagined as the steam rising from the spout.

α Sgr (Rukbat) is not the brightest star of the constellation, having a magnitude of only 3.96 (not shown on the main map as it is located below the map's southeastern corner, north is up).

The Milky Way as seen from the Earth 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 Messier 55, about 7.5° west of δ Sgr.

The constellation contains nebulae such as the Lagoon Nebula (Messier 8), near λ Sagittarii, beautiful in telescopes; the Omega Nebula (Messier 17), also known as the Swan or Horseshoe Nebula, near the border with Scutum; and the Trifid Nebula (Messier 20), a large nebula containing some very young, hot stars. The grouping of Lagoon Nebula, Trifid Nebula, and NGC 6559 is often called the Sagittarius triplet.

In 1999 a violent outburst at V4641 Sgr revealed the location of the closest known black hole to Earth.^[3]

The complex radio source Sagittarius A is also here. Astronomers believe that one of its components, known as Sagittarius A*, is associated with a supermassive black hole at the center of the galaxy.

The Sagittarius Dwarf Elliptical Galaxy is located just outside the Milky Way.

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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.^[4] Sometimes it is called the 'Teapot' as it looks like one. The Greeks identified such a figure as a centaur, whereas 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.

Main article: Sagittarius (astrology)

The Western astrological sign Sagittarius of the tropical zodiac (November 22–December 21) differs from the astronomical constellation and the Hindu astrological sign of the sidereal zodiac (December 18–January 18).

• Sagitta

• Ridpath, Ian; Tirion, Wil (2007). Collins Stars and Planets Guide. London: HarperCollins. ISBN 978-0007251209.. 

• The Deep Photographic Guide to the Constellations: Sagittarius
• Star Tales – Sagittarius

Astronomy | Constellations of the Zodiac | Astrology
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