Canis Major

star chart
CMa star chart (IAU and Sky & Telescope magazine, Roger Sinnott & Rick Fienberg)

One of the 88 IAU constellations. This is the (one and only) constellation of the Dog in ancient Greek astronomy.

Orion-Group of constellations on the Kugel Globe, drawing and animated GIF by SMH 2025.

Etymology and History

In Hellenistic times, Greek astronomy had only one constellation, the Dog, so there was no need to distinguish between a large and a small dog. According to Eratosthenes, this dog had the bright star Sirius on its tongue. Ptolemy in Roman times placed it on the dog's snout.

What is interesting about Sirius, however, is that today we use the Greek proper name from Hellenistic times. Ptolemy in Roman times called the brightest star of the constellation ‘the Dog’.

Origin of Constellation

Babylonian

Greco-Roman

Aratos

[326] Such is also his guardian Dog, seen standing on its two legs below the soaring back of Orion, variegated, not bright overall, but dark in the region of the belly as it moves round; but the tip of its [330] jaw is inset with a formidable star, that blazes most intensely: and so men call it the Scorcher. When Sirius rises with the sun, trees can no longer outwit it by feebly putting forth leaves. For with its keen shafts it easily pierces their ranks, [335] and strengthens some, but destroys all the growth of others. We also hear of it at its setting. The other stars lying round about Sirius define the legs more faintly. (Kidd 1997)

Eratosthenes
Hipparchus
Hyginus, Astronomica

He is said to have been given by Jove as a guardian for Europa, and later to have come to Minos. When Minos was ill, Procris, wife of Cephalus, is said to have cured him, and received the dog as a reward for her services, as she was very fond of hunting and the dog was so swift that no beast could escape. After her death the dog came to Cephalus her husband, who brought it to Thebes with him when he came. There was a fox there which was said to be so swift that it could outrun all dogs. So when the two animals met, Jupiter, in a dilemma, as Istros says, changed them both to stone.

Some have said that this is the dog of Orion, and because Orion was devoted to hunting, the dog was put with him among the stars. Others have called it the dog of Icarus. These many suggestions have their own advocates.

The Dog has one star on his tongue which itself is called Dog, and on its head another which Isis is thought to have put there under her own name, and to have called it Sirius on account of the brilliance of the flame because it seems to shine more than the rest. So, in order for men to recognize it more easily, she called it Sirius. (Mary Ward 1960)

Almagest Κύων
idGreek

(Heiberg 1898)

English

(Toomer 1984)

ident.
Κυνὸς ἀστερισμόςConstellation of the Dog
1ἐν τῷ στόματι λαμπρότατος καλούμενος Κύωυ καὶ ὑπόκιρρος.The star in the mouth, the brightest, which is called 'the Dog' and is reddishalf CMa
2ὁ ἐπὶ τῶν ὡτοη.The star on the earstet CMa
3ὁ ἐπὶ τῆς κεφαλῆThe star on the headgam CMa
4τῶν ἐκ τῷ τραχήλῳ β ὁ βόρειοςThe northernrriost of the 2 stars in the neckiot CMa
5ὁ φόσιος αὐτῶνThe southernmost of thempi CMa
6ὁ ἐπὶ τοῦ στήθους.The star on the chestnu3 CMa
7τῶν ἐπὶ τοῦ δεξιοῦ γόνατος β ὁ βόρειος.The northernmost of the 2 stars on the right kneenu2 CMa
8ὁ νοτιώτερος αὐτῶν.The southernmost of thembet CMa
9ὁ ἐπ’ ἄκρῳ τῷ ἐμπροσθίῳ ποδίThe star on the end of the front legxi1 CMa
10τῶν ἐν τῷ ἀριστερῷ γόνατι β ὁ προηγούμευος.The more advanced of the 2 stars in the left kneexi2 CMa
11ὁ ὁ ἐπόμενος αὐτῶνThe rearmost of themomi2 CMa
12τῶν ἐν τῷ ἀριστερῷ ὤμῳ β’ ὁ ἑπόμενος;The rearmost of the 2 stars in the left shoulderomi1 CMa
13ὁ προηγούμενος αὐτῶνThe more advanced of themdel CMa
14ὁ ἐν τῇ ἐκφύσει τοῦ ἀριστεροῦ μηροῦ.The star in the place where the 1eft thigh joins [the body)del CMa
15ὁ ὑπὸ τὴν κοιλίαν ἐν τοῦς μεσομήροιςThe star below the belly, in the middle of the thighseps CMa
16ὁ ἐπὶ τῆς ἀγκύλης τοῦ δεξιοῦ ποδόςThe star on the joint of the right legkap CMa
17ὁ ἐπ’ ἄκρου τοῦ δεξιοῦ ποδός.The star on the end of the right legzet CMa
18ὁ ἐπὶ τῆς οὐρᾶςThe star on the taileta CMa
ἀστέρες τῆ, ὥν αἱ μεγέθους ἂ, γ’ ἓ, δ’ ἓ, ε’ ξ.{18 stars, 1 of the first magnitude, 5 of the third, 5 ofthe fourth, 7 of the fifth}
Οἱ περὶ τὸν Κύνα ἀμόρφωτοι.
19ὁ ἀπ’ ἄρκτου τῆς κορυφῆς τοῦ Κυνός.The star to the north of the top of The Dog22 Mon
20τῶν ὑπὸ τοὺς ὀπισθίους πόδας ὡς ἐπ’ εὐθείας ὁ ὁ νοτιώτατος.The southernmost ofthe 4 stars almost on a straight line under the hind legsθ Col
21ὁ τούτου βορειότερος.The one north of thisκ Col
22ὁ ἔτι τούτου βορειότερος.The one north again of thisδ Col
23ὁ λοιπὸς καὶ βορειότερος τῶν δThe last and northernmost of the 4λ CMa
24τῶν πρὸς δυσμὰς τοῦς τέσσαρσιη ὡς ἐπ’ εὐθείας γ ὁ προἠγούμενοςThe most advanced ofthe 3 stars almost on a straightline to the west of the [ above] fourμ Col
25ὁ μέσος αὐτῶνThe middle oneλ Col
26ὁ ἑπόμευος τῶν τριῶν.The rearmost of the threeγ Col
27τῶν ὑπὸ τούτους β λαμπρῶν ὁ ἐπόμευος.The rearmost of thc 2 bright stars under theseβ Col
28ὁ προηγούμενος αὐτῶν.The more advanccd of themα Col
29ὁ λοιπὸς καὶ νοτιώτερος τῶν προειρημένων.The last star, to the south of the abovcε Col
allἀστέρες ἱα, ὥν β’ μεγέθους β, δ’ 9.{11 stars, 2 of the second magnitude, 9 of the fourth)

Transfer and Transformation of the Constellation

Mythology

Weblinks

References