Cassiopeia

Cassiopeia, the Queen, is an easily recognized constellation whose five brightest stars form a distinctive W or M shape depending on its position in the sky. As a circumpolar constellation for northern mid-latitudes, it is visible year-round. Tycho Brahe observed the supernova of 1572 (Tycho's Star) in Cassiopeia, which helped overturn the prevailing view that the heavens were unchanging.

The Perseus family groups constellations connected by the Greek myth of Perseus, the hero who slew Medusa and rescued Andromeda. This family includes some of the most prominent autumn constellations in the northern sky. The constellations tell a connected story: King Cepheus and Queen Cassiopeia of Ethiopia, their daughter Andromeda chained to a rock, the hero Perseus arriving on Pegasus, and Cetus the sea monster — all placed in the sky as a complete mythological tableau.

Mythology & History

The Perseus myth is one of the most complete stories preserved in the constellations. Cassiopeia's boast that she was more beautiful than the sea nymphs angered Poseidon, who sent Cetus to ravage the coast. The oracle declared Andromeda must be sacrificed, but Perseus — fresh from beheading Medusa — turned the monster to stone with the Gorgon's head. Perseus married Andromeda, and all the characters were later placed among the stars. The variable star Algol (Beta Persei) was associated with Medusa's winking eye, and its regular brightness changes were noted by ancient Egyptian astronomers as early as 1244 BC.

Observation Tips

The Perseus family constellations are best seen in autumn and winter from northern latitudes. Cassiopeia's distinctive W-shape is circumpolar from mid-northern latitudes and serves as a guide to finding the other family members. This region is exceptionally rich: the Andromeda Galaxy (M31) — the most distant object visible to the naked eye — lies in Andromeda, the Double Cluster (NGC 869/884) straddles Perseus, and the annual Perseid meteor shower (peaking in August) appears to radiate from Perseus.

HIP 7401HIP 7402HIP 7413HIP 7416HIP 7418HIP 7422HIP 7423HYG 118110HYG 118101HIP 7455HIP 7458HIP 7471HIP 7475HIP 7486HIP 9403HIP 9211HIP 9215HIP 9220HIP 8057HIP 9446HIP 9461HIP 9267HIP 9268HIP 7625HIP 9287HIP 9321HIP 7640HIP 7641HIP 7697HIP 5890HIP 3442HIP 9795HIP 981HYG 117997HYG 118021HYG 118043HYG 118099HYG 118188HYG 118193HYG 118195HYG 118234HIP 5903HIP 3472HIP 3544HIP 5908HIP 8305HIP 8307HIP 8312

Frequently Asked Questions

What is the Cassiopeia constellation?
Cassiopeia (Cas) is one of the 88 IAU-recognized constellations in the Northern hemisphere. Cassiopeia, the Queen, is an easily recognized constellation whose five brightest stars form a distinctive W or M shape depending on its position in the sky. As a circumpolar constellation for norther
How many stars are cataloged in Cassiopeia?
StarFYI currently catalogs 2,352 stars in the constellation Cassiopeia.
What is the brightest star in Cassiopeia?
The brightest star in Cassiopeia is Schedar.
How large is the Cassiopeia constellation?
Cassiopeia covers 598.41 square degrees of the sky.
What family does Cassiopeia belong to?
Cassiopeia belongs to the Perseus Family of constellations.