Generalities: it is perhaps the most beautiful constellation of the whole sky, for its peculiar form and  the presence of bright stars and interesting objects. It masters exactly the celestial equator. Its transit at midnight takes place in December.

Origins and mythology: it represents the mythical hunter who boasted to be able to kill any creature on the Earth. He was killed by a Scorpion that stung him. For this reason, Scorpion and Orion, harsh enemies, are in opposite points of the sky and they can never be seen contemporarily. After the deadly puncture Orion was revived by Esculapio, Apollo and Coronide's child , but he was definitely killed by Diana, the goddess of hunting, who saw in him a dangerous competitor for his hunting skills.

Stars: Orion shows two stars of the first magnitude. The former is Rigel, of white-blue color and magnitude 0.12, which is  at least 900 light-years far. This star is the seventh one of the whole sky for its brightness. The latter is the red Betelgeuse, of average magnitude 0.7 (it is a variable star), which is about 600 light-years far and it is the tenth star of the sky for its brightness. They complete the principal quadrilateral Bellatrix (m=1.64) and Saiph (m=2.06). Orion's belt (the three stars lined up with the center of the quadrilateral) includes Mintaka, Alnilam and Alnitak, of magnitudes 2.23, 1.70, 1.77 respectively.Orion includes eight stars under magnitude 3, and 15 under magnitude 4 altogether.

Other objects: in Orion the most famous and beautiful nebula is found, which can be observed even with common binoculars. Orion's nebula, listed as M42, is  between 1,600 and 1,900 light-years far and  is an area where new stars are being formed. In Orion the famous dark nebula "Horse Head" is also found, so called for its aspect; however, it can be shown only by long exposure photos .
 

Table of stars brighter than magnitude 3.5
 
 

Star	Proper name	Magnitude	Spectrum	Color	Distance (light-years)	Notes
Beta	Rigel	0.12 (variable)	B8	white	910
Alpha	Betelgeuse	0.5 (variable)	M2	red	600
Gamma	Bellatrix	1.64	B2	blue	360
Epsilon	Alnilam	1.70	B0	blue	1200
Zeta	Alnitak	1.77	O9.5	blue	1100
Kappa	Saiph	2.06	B0.5	blue	2100
Delta	Mintaka	2.23 (variable)	O9.5	blue	2350
Iota	Hatysa	2.76	O9	blue	1850
Pi 3		3.19	F6	white-yellow	25
Eta	Algiebbah	3.36 (variable)	B1	blue	750
Lambda	Heka	3.39	O8	blue	1800

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