Andromeda, the Chained Princess

Andromeda is a large northern constellation, one of Ptolemy's forty-eight, representing the princess of Greek myth who was chained to a rock as a sacrifice to the sea-monster Cetus and rescued by the hero Perseus, whom she married. She lies amid the whole cast of the story, her parents Cepheus and Cassiopeia, the hero Perseus, and the monster. The constellation is celebrated above all for the Andromeda Galaxy, the nearest large spiral galaxy to our own and the most distant object readily visible to the unaided eye, a faint smudge in dark skies. One of her stars is shared with the Great Square of Pegasus. In astronomical tradition the constellation is a pattern of stars rather than a zodiac sign. These are the features of Andromeda as the classical and modern traditions describe it, distinct from any astrological reading.

Andromeda's eastern edge borders Lacerta, the little lizard Hevelius introduced in 1687 to fill the narrow gap between Andromeda, Cepheus and Cygnus, one of the smallest and least storied of his seventeenth-century additions, with no myth attached to it beyond its plain descriptive name. The Andromeda Galaxy's light left its source well over two million years ago, so what is visible to the naked eye tonight is light that began travelling before the genus Homo itself had evolved, one of the more vivid ways to make its enormous distance concrete.