Cygnus

As is the case with so many of the constellations, there are a number of possible explanations for the presence of the swan in the heavens. Some myths, for instance, state the swan was once the pet of the Queen Cassiopeia. Other versions state that the swan was Cionus, son of Neptune, who was wrestled to the ground and smothered by Achilles. To save his son, Neptune immortalized Cionus as a swan.

Another story says the swan is Orpheus, who was murdered by the Thracian women while under the influence of Bacchus. Upon his death, the celebrated musician was placed in the heavens to spend eternity by his harp, Lyra. Yet another variant says that the swan represents the form taken by Jupiter when he deceived Leda and fathered Pollux.

According to Ovid, the swan was once Cygnus, son of Sthenele and a close friend of Phaethon. Phaethon died in the river Eridanus after attempting to drive the chariot of the sun, and Cygnus was overcome with grief that Jupiter could have struck down his friend:

As he mourned, his voice became thin and shrill, and white feathers hid his hair. His neck grew long, stretching out from his breast, his fingers reddened and a membrane joined them together. Wings clothed his sides, and a blunt beak fastened on his mouth. Cygnus became a new kind of bird: but he put no trust in the skies, or in Jupiter, for he remembered how that god had unjustly hurled his flaming bolt. Instead, Cygnus made for marshes and broad lakes, and in his hatred of flames chose to inhabit the rivers, which are the very antithesis of fire (Metamorphoses II 374-382).

Cygnus is easily found in the summer sky. Also called the Northern Cross because of its characteristic shape, its brightest star is Deneb, which is part of the Summer Triangle with Vega and Altair. Cygnus is located next to Cepheus and Lyra.