Bootes is one of the oldest recorded constellations. To find the Herdsman Bootes, follow the handle of the Big Dipper, which arcs southward to the bright star Arcturus, the brightest star in Bootes. The best time to view Bootes is during the spring and early summer. Modern astronomers see Bootes in the shape of a kite or an ice-cream cone. The star Arcturus lies at the bottom of the kite.
History and Mythology
Bootes is a constellation rich in history and mythology. He was the son of Demeter, the goddess of agriculture, and was credited with inventing the plow. Bootes was placed in the sky to honor this important invention.
Another myth is that Bootes represents Arcas, son of Zeus and Callisto. When Bootes' mother Callisto was changed into a bear by Zeus's jealous wife Hera, Arcas was sent to slay the bear, but Zeus prevented the tragedy by placing them both in the heavens. There, Hera became the constellation Ursa Major, the Great Bear.
Bootes is mentioned in the Odyssey as a bear driver chasing Ursa Major and Ursa Minor across the sky. The name Arcturus comes from the Greek for "guardian of the bear," and in some depictions, the constellation is seen as a bear-keeper, leading the Hunting Dogs of the nearby constellation Canes Venatici. Bootes drives the bears of Ursa Major and Ursa Minor around the pole.
The Greeks believed that Bootes was a herdsman named Icarius. He was a dear friend of the god of wine Dionysus. He was killed by enemies, and his body was hidden under a tree. Dionysus found his lost friend and honored him by placing him in the stars.
The Ancient Egyptians thought that the stars were evil because they never set. They saw Bootes as a hippopotamus which represented the incarnation of a goddess whose job was to keep the evil stars under control.
The Chinese saw the star Arcturus as one of the horns of a huge celestial dragon that ruled the spring sky. To this day, Chinese New Year parades portray this dragon chasing a pearl which represents the sun. If the dragon gets the pearl, then man can have his heart's desire, and the world is reborn.
Notable Stars
Arcturus is the fourth-brightest star in the night sky. Its name comes from the Greek "arktouros", meaning "guardian of the bear." Arcturus is also known as Job's Star. Arcturus is an orange giant with a magnitude of -0.04. Although cooler than the sun, it is 25 times larger and more than 200 times brighter. At 36 light-years away, Arcturus is the closest giant star to Earth.
Nekkar, or Beta Bootis, has an Arabic name meaning "the ox driver", and is a yellow giant with a luminosity of 190 Suns shining from a distance of 220 light years. Third magnitude Gamma Bootis, or Seginus, is a white giant star 85 light years distant; its name is a mistranslation of "Bootes" from Greek to Arabic to Latin.
Bootes contains a number of well-known double stars. Among these are Izar, or Epsilon Bootis, whose name means "girdle" or "loin cloth" in Arabic. Izar is one of the finest double stars in the sky; it consists of a magnitude 2.7 orange giant only 3 arcseconds away from a white, magnitude 5.1 star.
Another excellent double is Zeta Bootis, with nearly identical white components of magnitude 4.5. Their orbit is unusually eccentric; at closest approach they are nearly inseparable, but at their farthest separation - about 1.4 arcseconds, which will next come in 2082 - they are easily resolved.
Xi Bootis is a binary star system consisting of two sunlike stars only 22 light years away. Its 4th- and 7th-magnitude components appear anywhere from 2.5 to 7 arcseconds apart on their 150-year orbit.
Clusters, Nebulae, and Galaxies
NGC 5466 is a 9th-magnitude globular cluster with a rather loose, open structure. It can be resolved in a 10 inch telescope. NGC 5248 is a 10th magnitude spiral galaxy best seen in a 12 inch or larger instrument.
NGC 5248 is a very compact barred-spiral galaxy in the southwestern corner of Bootes. It has an apparent magnitude of 10.2 and an apparent diameter of 6.5'.