Celestial, Map, from the golden age of, Netherlandish, cartography, by the Dutch cartographer Frederik de Wit.
A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.
The 88 modern constellations are formally defined regions of the sky together covering the entire celestial sphere.
The origin of the earliest identified constellations likely dates back to prehistory, when they may have related to beliefs, experiences, creations, or mythology. Different cultures adopted their own sets of constellations outlines, some of which persisted into the early 20th century.
Constellations have significantly changed throughout the centuries. Many have varied in size or shape, with some becoming popular then dropping into obscurity, or others being traditionally used only by various cultures or single nations.