A pair of hunting dogs chases high across the north on May evenings. The hounds are pursuing Ursa Major, the great bear, which stands below them at nightfall. You’ll recognize the bear because it contains the stars of the Big Dipper. The dogs are held in leash by Boötes, the herdsman.
The dogs form the constellation Canes Venatici. Unlike Ursa Major and Boötes, which date from antiquity, the hunting dogs are fairly recent. Polish astronomer Johannes Hevelius drew the constellation in the 17th century to fill in some gaps between more prominent star patterns.
As a result, Canes Venatici is small and faint. You need fairly dark skies to see its stars, and a great imagination to picture a pair of hounds. The constellation’s three brightest stars form a wide-spread letter V, with its point aiming south.
Canes Venatici’s brightest star is Cor Caroli — the “heart of Charles.” Famed astronomer Edmond Halley named it for England’s King Charles the Second. Binoculars or a telescope show that it’s really two stars. The brighter one is hotter and brighter than our own Sun, and it’s the star that’s visible to the eye alone.
The constellation’s next-brightest star is Chara, and it’s similar to the Sun. It’s about the same color, temperature, and brightness. In fact, it looks almost exactly like the Sun would appear if we could view it from the same distance — about 30 light-years.
Look carefully for the stars of the hunting dogs as they pursue the great bear across the night.
Script by Damond Benningfield, Copyright 2013
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