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 3462HIP 3437HIP 3440HIP 2749HIP 838HIP 8385HIP 3499HIP 3500HIP 3501HIP 8396HIP 2760HIP 3507HIP 6863HIP 5147HIP 3509HIP 8626HIP 9704HIP 2768HIP 2770HIP 3638HIP 3641HIP 3649HIP 8629HIP 8630HIP 2772HIP 8632HIP 2778HIP 3668HIP 3688HIP 3689HIP 3690HIP 2779HIP 278HIP 352HIP 4871HIP 4872HIP 8164HIP 8165HIP 8166HIP 2782HIP 3736HIP 3742HIP 279HIP 2791HIP 9720HIP 9726HIP 4875HIP 3818

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.