Generalities: it is a constellation that characterizes deeply the southern sky. It is  the smallest constellation of the whole sky, but it is among the most famous ones  for its beauty and for its peculiar form. It doesn't show the exact direction of the celestial south pole, as many people believe. In fact the  Southern Cross  turns around the celestial south pole, like the Big Bear does around the celestial north pole. Its direction is therefore only indicatively south. Its transit at midnight takes place in April.

Origins and mythology: obviously it doesn't have any mythological links, since it was introduced by Royer in modern times. This group of bright stars had initially been inserted in the constellation of the Centaur, only later it was considered a real constellation.

Stars: the Southern Cross contains four bright stars arranged as a quadrilateral. Three of these stars are under  magnitude 2, while the fourth one is of magnitude 2.8, slightly variable. The star alpha has magnitude 0.83 and is the fourteenth star of the whole sky for brightness. It has white-blue color and it is a double star that can be observed by amateur tools. Its name is Acrux, it is about 350 light-years far. The stars beta and gamma, of magnitude 1.25 and 1.63 respectively, are different for color: the former is white-blue, the latter is red. Their names are Mimosa and Gacrux. They occupy the twentieth  and the twenty-third position for brightness.
 

Table of stars brighter than magnitude 3.5
 

Star	Proper name	Magnitude	Spectrum	Colour	Distance (light-years)	Notes
Alpha	Acrux	0.83 (1.41+1.88)	B1+B3	blue	350	Visual double star
Beta	Mimosa (Becrux)	1.25 (variabile)	B0	blue	420
Gamma	Gacrux	1.63	M3	red	88
Delta		2.80 (variabile)	B2	blue	258

Other objects: in the Southern Cross a beautiful open cluster is present, called jewel-case for the beauty of its stars, together with a famous dark nebula, called "coal sack."

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