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 7173HIP 3346HIP 3347HIP 825HIP 9765HYG 117958HYG 117965HIP 3348HIP 3349HYG 117982HIP 902HIP 7215HIP 7224HIP 7232HIP 7238HIP 7246HIP 7247HIP 7248HIP 7249HIP 7251HIP 7253HIP 3868HYG 117989HYG 117993HYG 118003HYG 118005HYG 118007HYG 118008HIP 7301HIP 9956HIP 9958HIP 9042HYG 118028HYG 118032HYG 118033HYG 118035HYG 118037HIP 9057HIP 9081HIP 9962HIP 9131HYG 118077HYG 118083HYG 118090HYG 118091HIP 917HIP 3383HIP 7400

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.