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 2921HIP 2922HIP 5421HIP 5151HIP 5232HIP 5508HIP 5523HIP 5247HIP 5251HIP 5252HIP 3532HIP 2930HIP 3533HIP 2932HIP 8231HIP 2935HIP 5566HIP 5569HIP 5576HIP 5582HIP 5587HIP 4627HIP 466HIP 4634HIP 4635HIP 4636HIP 4637HIP 4650HIP 2951HIP 4674HIP 4679HIP 4680HIP 4683HIP 4709HIP 4713HIP 4714HIP 472HIP 4717HIP 4740HIP 475HIP 4744HIP 4755HIP 4757HIP 4758HIP 4760HIP 4766HIP 4781HIP 4782

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.