Sagittarius, the Archer, is a zodiacal constellation that lies in the direction of the center of our own Milky Way Galaxy. It lies on the ecliptic in between Scorpius and Capricornus. Hold your mouse cursor over the image to see constellation figures, boundaries, and star identifications. Stylized drawings of the mythological figure of Sagittarius show a centaur drawing a bow and arrow aimed at the heart of Scorpius, the Scorpion. The constellation of Sagittarius is the current location of the December solstice. This is the point in the sky where the Sun is farthest south from the celestial equator, usually occurring around December 22. On this day, the Sun is lowest in the sky at local solar noon for the northern hemisphere of Earth marking their first day of winter, and highest in the sky for the southern hemisphere marking their first day of summer. This is also the shortest day of the year for the northern hemisphere and longest day of the year for the southern hemisphere. On this day, the Sun rises farthest south of due east, and sets farthest south of due west. For observers north of 66.56° north latitude (the Arctic Circle) in the northern hemisphere, the Sun never rises above the horizon all day during the northern winter. For observers south of 66.56° south latitude (the Antarctic Circle) in the southern hemisphere, the Sun is above the horizon all day during the southern summer. The Sun is located in the constellation of Sagittarius from December 18 to January 20. Alpha Sagittarii, Rukbat, is a 4th magnitude star that is not seen in the image above because it is out of the bottom of the frame to the south. The Teapot asterism defines the most prominent stars in Sagittarius. It is comprised of Tau, Sigma, Phi, Zeta, Lambda, Delta, Epsilon and Gamma Sagittarii. Epsilon Sagittarii is Kaus Australis, the brightest star in the constellation at an apparent visual magnitude of 1.8. It is a spectral-type B blue-giant star that lies 143 light-years away. Sagittarius is home to 15 Messier objects, the brightest of which include M8 (the Lagoon Nebula), M20 (the Trifid Nebula), M17 (the Omega Nebula), M24 (the Small Sagittarius Star Cloud), open clusters M18, M21, M23, M25, and globular clusters M22, M28, M54, M55, M69, M70 and M75. Sagittarius was cataloged by the Greek astronomer Ptolemy in the second century C.E. (Common Era). It is the 15th largest of today's 88 modern constellations, covering 867 square degrees of sky. North is to the top in the above image.
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