Crux is a constellation centred on four stars in the southern sky in a bright portion of the Milky Way. It is among the most easily distinguished constellations as its hallmark (asterism) stars each have an apparent visual magnitude brighter 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.

Predominating the constellation is the first-magnitude blue-white star of α Crucis (Acrux), its brightest and most southerly member. There follow four less dominant stars which appear clockwise and in order of lessening magnitude: β Crucis (Mimosa), γ Crucis (Gacrux), δ Crucis (Imai) and ε Crucis (Ginan). Many of these brighter stars are members of the Scorpius–Centaurus Association, a large but loose group of hot blue-white stars that appear to share common origins and motion across the southern Milky Way.

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