Sagittarius is the ninth sign of the zodiac. Because this constellation is located low in the sky, you can view it best where there is a clear southern horizon during the summer months. It has a very distinctive shape; some call it a teapot because of the outline found in the middle area of the constellation, as shown in image on your right.
Sagittarius has plenty of interesting viewable objects that will draw the interest of any backyard astronomer. In the Northern hemisphere, the Sagittarius constellation appears during the early morning hours of the spring and vanishes from sight in the autumn. At no other place in the sky is the glow of the Milky Way as strong as in the Sagittarius region. When looking at constellation Sagittarius, our eyes are looking towards the center of our Milky Way galaxy.
Constellation Sagittarius Mythology
The constellation has its roots in Sumerian culture, but is traditionally depicted as a centaur, half-man, half-horse found in Greek myths. This centaur, named Chiron was the son of the titan Cronos and the nymph Philyra. Chiron was good natured, unlike most centaurs who were violent. He is depicted wearing a cloak and drawing his bow, aiming an arrow at the star Antares, which represents the heart of the Scorpio constellation. As such, he is often called “The Archer”. After Hercules accidentally wounded him, Zeus saw that Chiron was in great pain and let him die and then placed him in the heavens.
Stars and DSO’s in Constellation Sagittarius
Sagittarius is the constellation that contains the greatest number of stars with known planets. It contains many bright stars. The brightest ones are The brightest ones  delta,  epsilon,  zeta,  phi,  lambda,  gamma-2,  sigma and  tau Sagittarii. These are the stars that form the Teapot asterism.
Another star of interest in Sagittarius is the Pistol Star. It is a bright blue hypergiant, a variable star, that is one of the most luminous stars discovered in the Milky Way. You cannot see it with the naked eye because it is hidden by a cloud of interstellar dust that surrounds it. Yet the Pistol Star is amongst the brightest of our galaxy.
Constellation Sagittarius is filled with interesting deep sky objects. Popular sights include one of the brightest star clusters in the region: Messier 55, or NGC 6809, located near  delta Sagittarii.
The Omega Nebula, or Messier 17 (NGC 6618) gives birth to new stars. The nebula contains about 35 young stars. These radiate energy and produce a reddish glow in the nebula. The stars themselves are hidden in the nebulosity and cannot be observed. The Omega Nebula is known by many names including the Swan Nebula, the Horseshoe Nebula and the Lobster Nebula.
The Trifid Nebula, or Messier 20 (NGC 6514), is another hot spot for star formation within Sagittarius. It contains a reddish emission nebula, a blue reflection nebula, a dark nebula, and an open cluster of stars. The name Rrifid means “divided into three lobes.” In 2005, the NASA Spitzer Space Telescope made an interesting observation. It discovered 30 embryonic stars as well as 120 newborn stars inside the nebula.
The Sagittarius Dwarf Elliptical Galaxy is on of the closest satellite galaxies of the Milky Way. It contains at least four globular star clusters. Messier 54 (NGC 6715) is located in the center of the galaxy and was the first globular cluster ever discovered outside the Milky Way. It is located near  zeta Sagittarii.
Great Telescopes to View Sagittarius DSO’s
Orion SkyView Pro 8″ Equatorial Reflector Telescope
Orion SkyQuest XT10g Computerized GoTo Dobsonian Telescope
Celestron NexStar 8SE GoTo Schmidt-Cassegrain Telescope