Sagittarius is a constellation of the zodiac, one of the 13 constellations that are blocked out by the sun at a certain time of the year, namely summer. The sun covers it during later November through December, and is visible at our latitude during the month of August, around 9pm. It is at 19 hours ascension and -25 degrees declination. Sagittarius is one of the gateways into the center of the galaxy- the milky way is the densest as it is seen through the constellation. It also has 3 nebulae- the Omega (Swan or Horseshoe nebula) nebula, the Trifid Nebula, and the Lagoon Nebula. There is also a possible black hole somewhere around there as well.
Sagittarius comes from the Greek mythology of an centaur archer- the name is “archer” in Latin: the Babylonians though Sagittarius to be the god Pabilsag, an archer, shaped like a centaur-like creature. In many images of this beast, it has 2 heads, wings, one human head and one panther head, a horse tail, AND a scorpion tail. The Babylonian name comes from “Pabil” and “Sag”, names that elude to “chief ancestor” in meaning. In greek mythology, it is just a centaur- a half-man, half-horse beast. It is said that Sagittarius used to be a centaur at some point but then changed himself into a horse in order to escape a jealous wife. The “arrow” of the constellation points toward the heart of the scorption, or the star “Antares”.
It has 9 bright stars, but only 6 will be discussed. Delta Sagittari, which is 306 light years from earth and has an apparent magnitude of +2.72, has a spectral type of K3. Zeta Sagittari has a spectral class of A2 and an apparent magnitude of +3.26 and is about 90 light years from Earth. Phi Sagittari is a spectral type B8 star with an apparent magnitude of +3.17 and is about 231 light years away from Earth. Lambda Sagittari (also called Kaus Borealis) has a spectral class of K, is 77 light years away from Earth, and has an apparent magnitude of +2.82. Gamma Sagittari has a spectral type of K and is about 95 light years from earth, with an apparent magnitude of +2.98. Epsilon is a binary star that has an apparent magnitude of 1.79, and it resides 145 light years away with a spectral type of B9.5. Epsilon also has a smaller neighbor star called Epsilon Sagittarii B, with a very feint magnitude.
Absolute Astronomy, http://www.absoluteastronomy.com/topics/Sagittarius_(constellation) -
Deepsky: http://deepsky.astroinfo.org/Sgr/ (yes, it's in German. The browser I use atomatically translates things.)
Ridpath, Ian; Tirion, Wil (2007). Stars and Planets Guide. Princeton: Princeton University Press.
http://www.allthesky.com/constellations/preview/sagittarius28vm.jpg - IMAGE of Sagittarius.
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