Generalities: it is included between the Head and the Tail of the Snake, the only constellation broken into two parts. It is a big constellation mastering the celestial equator but prominently situated in the southern hemisphere. Even if it isn’t included among the constellations of the zodiac, it can be considered  the thirteenth zodiacal constellation, as it is crossed by the Sun in the first half of December.
The transit at midnight takes place in June.

Origins and mythology: it represents Esculapio, the child of Apollo and Coronide. Esculapio was instructed in the medical art by the centaur Chiron and it became so skilled  to succeed in recalling the dead to life. Zeus eliminated him with a lightning because he feared the depopulation of  Ade. The snake represents  Esculapio’s shrewdness or perhaps his ability to save the one who had been  biten by poisonous snakes. The serpent has still remained the symbol of the medical profession.

Stars: the Ophiucus  shows 5 stars under  magnitude 3 and other seven under  magnitude 4. The brightest star of this constellation is called Ras Alhague, it has magnitude 2.08 and it is of white color. It is 60 light-years far.

Table of stars brighter than magnitude 3.5
 

Star	Proper name	Magnitude	Spectrum	Colour	Distance (light-years)	Notes
Alpha	Ras Alhague	2.08	A5	white	62
Eta	Sabik	2.43	A2	white	59
Zeta	Han	2.56	O9.5	blue	555
Delta	Yed Prior	2.74	M1	red	140
Beta	Cebalrai	2.77	K2	orange	120
Kappa		3.20	K2	orange	117
Epsilon	Yed Posterior	3.24	G8	yellow-orange	104
Theta		3.27	B2	blue	590
Nu		3.34	K0	orange	137

Other objects: in the Ophiucus different interesting objects are present. Nine globular clusters catalogued by Messier are present in this constellation: they are M9, M10, M12, M14, M19, M62 and M107.

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