IAU Recognized

The constellations are the named patterns into which the stars are grouped. Modern astronomy recognises eighty-eight, with boundaries fixed by the International Astronomical Union in the 1920s, dividing the whole sky between them; the classical set of forty-eight comes from Ptolemy's Almagest, and other cultures divided the sky in their own ways.

Each constellation carries a name and, usually, a myth explaining the figure it depicts, Orion the hunter, the Great Bear, the hero Perseus and the monster Cetus. The twelve zodiacal constellations are those the Sun's path crosses, and are the source of the names of the astrological signs, though signs and constellations no longer coincide.

The constellations belong to astronomy and to the mythologies that named them, and this category treats them as star patterns and as bearers of myth, distinct from the astrological signs that borrowed their names. Many cultures (Chinese, Indian, Mesopotamian, Polynesian and others), mapped the sky differently, and the Western forty-eight are one scheme among several.

The atlas gives each constellation its figure, its principal stars, and the myth or lore attached to it. The individual named stars within them are treated in the star category, and the zodiacal signs, which share their names, under the sign category.