Bootes the Herdsman is a Northern Hemisphere constellation best seen in the late spring. While it is one of the largest constellations in the sky, ranking 13th out of 88, it has no deep-sky wonders that are easily accessible. Bootes is best know for its stars and easy-to-spot shape.
Locating the Constellation Bootes
Bootes can be found south of Ursa Major the Great Bear, off the handle of the Big Dipper. Bootes's brightest star, Arcturus, is part of a mnemonic device used to orient people to the night sky. Because the Big Dipper is easy for most observers to find, the handle of the dipper is used to point to other important stars. The saying goes, "Arc to Arcturus, speed on down to Spica." This means that as you follow the curve in the dipper's handle away from Ursa Major you will run into a bright star, and this is Arcturus in Bootes. The other star mentioned in the saying is Spica, which is a part of Virgo.
Tracing Out the Shape of Bootes
Bootes is supposed to be the figure of a man, which is somewhat recognizable with its tall diamond shape and two stick legs jutting out at the bottom. The point at which the tall diamond shape and stick legs intersect is the star Arcturus. The Herdsman also appears to have his left arm raised over his head.
The Stars in the Herdsman
Arcturus, the brightest star in Bootes, shines at magnitude -0.05. Arcturus is the fourth brightest star in the night sky.The name Arcturus means "bear watcher" or "bear guard." Lying 37 light-years away, Arcturus (or Alpha Bootis) glows with a faint orange hue.
The second brightest star in Bootes lies on the left side of the diamond shape. Ten degrees up from Arcturus is where you will find Izar, or Epsilon Bootis, a magnitude 2.35 star lying much farther away, at 210 light-years.
The third brightest star in Bootes is his left knee, which is found to the lower right of Arcturus (assume that all objects in the sky are facing you, the observer). This star is Muphrid, or Eta Bootis, at magnitude 2.68. Muprhid lies 37 light-years away.
The other stars in the body of the Herdsman are all of comparable brightness. Starting above Izar and working up, around and back toward Arcturus are the stars Delta Bootis, Beta Bootis (or Nekkar - and consider this Bootes' neck), Gamma Bootis (or Seginus), and Rho Bootis.
Delta Bootis shines at magnitude 3.46 at a distance of 117 light-years. Nekkar shines at magnitude 3.49 and lies 219 light-years distant. Seginus has the brightest magnitude of these four stars, at 3.04. It is also closest of the four at 84 light-years. Finally, Rho Bootis, which lies almost even with Izar, shines at magnitude 3.57 and lies 149 light-years away.
