Crux is a constellation located in the southern sky in a bright portion of the Milky Way. It is among the most easily distinguished constellations, as none of its four main stars has an apparent visual magnitude fainter than +2.8, even though it is the smallest of all 88 modern constellations. Its name is Latin for cross, and it is dominated by a cross-shaped or kite-like asterism that is commonly known as the Southern Cross.

In modern astronomy, the sky (celestial sphere) is divided into 88 regions called constellations, generally based on the asterisms (which are also called "constellations") of Greek and Roman mythology. Those along the ecliptic are the constellations of the zodiac.

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