( that was introduced by
Johannes Hevelius in the
17th Century . It represents the dogs ''Chara'' and ''Asterion'' held on a leash by
Boötes .
Canes Venatici is one of three constellations that represent dogs, along with
Canis Major and
Canis Minor . The constellation's brightest
Star is
Cor Caroli (α
2 CVn), named by
Edmund Halley in memory of the king
Charles I ,
King Of England , or his son,
Charles II . It is of
Magnitude 2.90.
La Superba (Y CVn) is a
Semiregular Variable Star that varies between magnitudes 4.7 and 6.2 over a period of around 158 days. It is a
Carbon Star and is famous for being deep red.
AM CVn , a very blue star of magnitude 14, is the prototype of a special class of
Cataclysmic Variable Star s, in which the companion star is a
White Dwarf , rather than a
Main Sequence Star .
Canes Venatici contains five
Messier Object s, including four
Galaxies . One of the more significant galaxies in Canes Venatici is the
Whirlpool Galaxy (M51, NGC 5194) and
NGC 5195 , a small barred
Spiral Galaxy that is seen face on. This was the first galaxy recognised as having a spiral structure, this structure being first observed by
Lord Rosse in
1845 .
Other notable spiral galaxies in Canes Venatici are the
Sunflower Galaxy (M63, NGC 5055),
Messier 94 (NGC 4736), and
Messier 106 (NGC 4258).
Messier 3 (NGC 5272) is a
Globular Cluster . It is 18° in diameter, and at magnitude 6.3 is bright enough to be seen with
Binoculars .
The name of the ''hastile habens canes'' = "spearshaft having dogs", which expression floated about the astronomical literature until
Hevelius decided to find those dogs in the sky.
The northern of the two hunting dogs was named ''Asterion'', and was sometimes regarded as an independent constellation or at least an asterism. The southern dog was named ''Chara''. The name of the dogs still lives in the alternate names of
α CVn .
The star -->
- Ian Ridpath and Wil Tirion (2007). ''Collins Stars and Planets Guide'', HarperCollins, London. ISBN 978-0007251209.
