Diamond Cross ( Eng. Diamond Cross ) - asterism in the circumpolar southern constellation of Carina . The Diamond Cross consists of four bright stars : Beta Carina , Theta Carina , Ypsilon Carina and Omega Carina .
Asterism got its name due to the fact that the four stars that form it create an almost perfect rhombus in shape. When a diamond has the correct shape from nature, then, due to the properties of the diamond crystal lattice, the shape will be one of the variants of the octahedron , which has a rhombic section; Also, historically, one of the earliest and easiest ways to cut a diamond was to give an octahedron shape to diamonds (see Rose Cut ). Therefore, in English, the word diamond (diamond, diamond) often means the figure "diamond." Thus, in the English name Diamond Cross, the double meaning is played up: Cross-Rhombus / Diamond Cross .
Fully asterism is visible to all observers south of 20 ° . sh. In form, asterism bears a great resemblance to the constellation Southern Cross and asterism False Cross : all three have the form of a rhombus without a central star. As with the False Cross, asterism can be accepted by an inexperienced observer of the Southern Cross, albeit to a lesser extent than the False, since the Diamond Cross has a greater southern declination than the stars of the present Southern Cross.