Sagittarius

English name Archer

Major
stars gamma Sagittarii Alnasl magn. 3,1 RA: 18h 05m 48.50s Dec: -30° 25' 26.3"
delta Sagittarii Kaus Media magn. 2,8 RA: 18h 20m 59.67s Dec: -29° 49' 41.3"
epsilon Sagittarii Kaus Australis magn. 1,9 RA: 18h 24m 10.38s Dec: -34° 23' 04.6"
zeta Sagittarii Ascella magn. 2,7 RA: 19h 02m 36.71s Dec: -29° 52' 49.1"
eta Sagittarii magn. 3,2 RA: 18h 17m 37.66s Dec: -36° 45' 41.8"
lambda Sagittarii Kaus Borealis magn. 2,9 RA: 18h 27m 58.26s Dec: -25° 25' 17.7"
pi Sagittarii magn. 3,0 RA: 19h 09m 45.84s Dec: -21° 01' 24.9"
sigma Sagittarii Nunki magn. 2,0 RA: 18h 55m 15.92s Dec: -26° 17' 48.1"
tau Sagittarii magn. 3,4 RA: 19h 06m 56.42s Dec: -27° 40' 13.0"
phi Sagittarii magn. 3,3 RA: 18h 45m 39.37s Dec: -26° 59' 26.8"

Description Constellation of the zodiac, through which the Sun transits from the end of December to the end of January. It is to the northeast of Scorpius. Sagittarius contains many stars of average magnitude, but it is remarkable in particular for the great quantity of clusters and nebulas.
The principal open clusters are in the northern zone of the constellation. M23 is an ample cluster composed by hundred stars, some of which reach the ninth magnitude: it is visible with good binoculars. M24 is really a zone of the Milky Way in which many stars are assembled in perspective. M25, finally, is a rather diffused cluster, composed by about 50 stars distributed around a yellow supergiant.
To south the of M25 there is M22 a globular cluster of sixth magnitude: seen with small telescopes it appears of elliptical shape, while to resolve the single stars you need a telescope of average power.
Near the border with Ophiuchus there is M8, the Lagoon Nebula (on the left): it is visible to the naked eye as an out-of-focus spot; modest M20 instrments allow to see a dark trace that cuts into halves the nebula and that gives it the name. A little northwards there is M20, the very beautiful and very famous Trifid Nebula (on the right), which takes the name from the characteristic strips of dust that seem to divide it into three portions. On the border with Scutum and Serpens, finally, there is M17, that because of its circular shape is denominated in many ways: Omega Nebula, Swan Nebula or Horse-shoe Nebula.

Mythology
and history The constellation is identified with a centaur which bends a bow toward the near Scorpius: it is therefore the second centaur of the sky (the other one is just Centaurus).
According to the version of Eratostenes, instead, the constellation represents Crotus, a satyr son of Pan: the satyrs were fantastic creatures with human bodies, two equine legs, tail and small horns. Crotus was the inventor of the bow (for this reason in the sky he bends a bow) and he loved to spend the time with the nine Muses, the divinities of arts: amused by his company, they asked Zeus to give him a place among the stars.

English name	Archer

Major stars	gamma Sagittarii	Alnasl	magn. 3,1	RA: 18h 05m 48.50s	Dec: -30° 25' 26.3"
	delta Sagittarii	Kaus Media	magn. 2,8	RA: 18h 20m 59.67s	Dec: -29° 49' 41.3"
	epsilon Sagittarii	Kaus Australis	magn. 1,9	RA: 18h 24m 10.38s	Dec: -34° 23' 04.6"
	zeta Sagittarii	Ascella	magn. 2,7	RA: 19h 02m 36.71s	Dec: -29° 52' 49.1"
	eta Sagittarii		magn. 3,2	RA: 18h 17m 37.66s	Dec: -36° 45' 41.8"
	lambda Sagittarii	Kaus Borealis	magn. 2,9	RA: 18h 27m 58.26s	Dec: -25° 25' 17.7"
	pi Sagittarii		magn. 3,0	RA: 19h 09m 45.84s	Dec: -21° 01' 24.9"
	sigma Sagittarii	Nunki	magn. 2,0	RA: 18h 55m 15.92s	Dec: -26° 17' 48.1"
	tau Sagittarii		magn. 3,4	RA: 19h 06m 56.42s	Dec: -27° 40' 13.0"
	phi Sagittarii		magn. 3,3	RA: 18h 45m 39.37s	Dec: -26° 59' 26.8"

Description	Constellation of the zodiac, through which the Sun transits from the end of December to the end of January. It is to the northeast of Scorpius. Sagittarius contains many stars of average magnitude, but it is remarkable in particular for the great quantity of clusters and nebulas. The principal open clusters are in the northern zone of the constellation. M23 is an ample cluster composed by hundred stars, some of which reach the ninth magnitude: it is visible with good binoculars. M24 is really a zone of the Milky Way in which many stars are assembled in perspective. M25, finally, is a rather diffused cluster, composed by about 50 stars distributed around a yellow supergiant. To south the of M25 there is M22 a globular cluster of sixth magnitude: seen with small telescopes it appears of elliptical shape, while to resolve the single stars you need a telescope of average power. Near the border with Ophiuchus there is M8, the Lagoon Nebula (on the left): it is visible to the naked eye as an out-of-focus spot; modest instrments allow to see a dark trace that cuts into halves the nebula and that gives it the name. A little northwards there is M20, the very beautiful and very famous Trifid Nebula (on the right), which takes the name from the characteristic strips of dust that seem to divide it into three portions. On the border with Scutum and Serpens, finally, there is M17, that because of its circular shape is denominated in many ways: Omega Nebula, Swan Nebula or Horse-shoe Nebula.

Mythology and history	The constellation is identified with a centaur which bends a bow toward the near Scorpius: it is therefore the second centaur of the sky (the other one is just Centaurus). According to the version of Eratostenes, instead, the constellation represents Crotus, a satyr son of Pan: the satyrs were fantastic creatures with human bodies, two equine legs, tail and small horns. Crotus was the inventor of the bow (for this reason in the sky he bends a bow) and he loved to spend the time with the nine Muses, the divinities of arts: amused by his company, they asked Zeus to give him a place among the stars.

Sagittarius

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