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 11410HIP 1104HIP 114158HIP 114160HIP 114163HIP 14000HIP 175HIP 1105HIP 1401HIP 14011HIP 14019HIP 14049HIP 1405HIP 11058HIP 14094HIP 11067HIP 1762HIP 11070HIP 14108HIP 114465HIP 14133HIP 14142HIP 14149HIP 1415HIP 14154HIP 14160HIP 14166HIP 14167HIP 1417HIP 14184HIP 142HIP 14205HIP 14206HIP 14208HIP 14209HIP 14216HIP 1773HIP 14221HIP 115596HIP 1774HIP 115689HIP 115872HIP 115905HIP 115939HIP 115980HIP 116046HIP 116089HIP 116134

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.