Abbreviation:

Boo

English name:

Bear Driver

Coordinates

see Stellar data

Particulars:

• Double stars epsilon Boo, zeta Boo, kappa Boo, mu Boo, nu1/n2 Boo, pi Boo, xi Boo
• Variable stars W Boo, 44 Boo
• Meteor Shower January Bootids, June Bootids, Quadrantids

General:

A quite large constellation of the northern hemisphere. The fourth brightest star in the sky belongs to Boötes: Arcturus, a red giant of -0.04 mag. The name of this star has the meaning of the whole constellation: Bear Driver. Sometimes Boötes is also called Herdsman.
This constellation reaches as high as DECL=+55 degrees; the southern boundary reaches with DECL=+8 degrees nearly the celestial equator. From west to east Boötes extends from RA=13h 40m to RA=15h 50m. Although Boötes is mythologically connected to Ursa Major only the north-western edge is touch with the Great Bear. The other neighbouring constellation are: Canes Venatici and Coma Berenices to the west; Virgo to the south, Serpens, Corona Borealis and Hercules to the east and finally Draco at the other northern edge.

Stars and objects

The double epsilon Boo (a 9372), with the beautiful name Izar of Pulcherrima, is a glorious pair, but difficult to resolve. The K0 giant of 2.7 mag and its A2 main sequence companion of 5.12 mag can be split in a telescope with an aperture of at least 75mm and good optics. The contrasting colours make them to an interesting object to observe. The two stars orbit each other with a period of 153 years.
Very close to epsilon Boo lies the variable star W Boo, a M3 giant of 4.81 mag.
A very close double is zeta Boo. The two A2 giants of 4.43 mag and 4.83 mag need telescopes with an aperture of at least 120mm to resolve the components. The two stars revolve each other with a period of 130 years.
Another nice, white-yellowish pair is kappa Boo: The A8 subgiant of 4.54 mag and the F1 main sequence star of 6.69 mag should resolve fine in small scopes.
A binocular is sufficient to see the 6.5 mag companion (spectraltype G1V) of mu Boo, also called Alkalurops an F0 main sequence star of 4.31 mag. They have an orbiting period of 224 years. Using a telescope with an aperture of 75mm or higher and high magnification the companion reveals itself also as a double.
The pair nu1/nu2 Boo only seems to be a double star. The two unrelated 5th mag stars (a K5 giant and a A5 main sequence star) split easily in small scopes.
Pi Boo (a 9338) is a wide, easy to observe visual binary. The two stars are an A6 main sequence star of 5.81 mag and a B9pMnHg of 4.94 mag.
Another beautiful pair for small scopes is xi Boo. Its consists of an yellow and an orange star of 5th and 7th mag.
The variable star 44 Boo (a 9494) is an eclipsing binary and well worth being paid attention.
Three meteor showers are associated with Boötes:
The January Bootids have a quite short duration; falling from January 9th to January 18th, they shower activity reach its maximum on January 18th.
The June Bootids are also called Pons-Winneckids. This meteor shower is active from June 27th to July 5th. The maximum occurs shortly after the beginning of the activity, on 28th of June, with only one or two meteors per hour.
From the northern part of Boötes radiates the meteor shower Quadrantids from 28th of December to 7th of January. On January 3rd-4th they reach their maximum with about 100 meteors per hour. Detailed information about this strongest meteor shower can be found in Gary Kronk's database.

Mythological Background:

According to Ovid's (Publius Ovidius Naso; 43 BC to 17 AC) Metamorphoses, is Callisto's son Arkas the Bear Driver. Callisto has been changed to a bear (see the story in description of Ursa Major). To prevent Arkas from killing his mother (which he did not recognize), Zeus took both an made them neighbouring constellations.
Eratosthenes of Cyrene (230 B.C.) tells the story in his Catasterismi (8) a little bit different: Arkas has been the son of Lykaon, who sacrificed him and gave him Zeus with the meal in order to test, if the god is really allknowing. Zeus, of course, knew immediately the truth and punished the cruel father. After that he set father and son under the stars.