| CASSIOPEIA Chart | Midnight Culmination | Skylore | Description | Special Stars |
| Star Clusters | Discussed in these Shows |

Constellation Data

  • Translation: Ethiopian Queen
  • Abbreviation: Cas
  • Genitive: Cassiopeiae
  • Size: 25
  • Regions: Circumpolar
  • RA: 1hour
  • Decl: +60 degrees
  • Season: Anytime
  • Midnight Culmination: 9 October
  • Pages where CASSIOPEIA is discussed in Chet Raymo's 365 Starry Nights: 169,184-188

What is the Genitive form?
What is Right Ascension (RA)?
Is this constellation ever visible from my latitude? What is Declination?

Where should I look for a constellation on a date before or after its midnight culmination? What is Midnight Culmination?


Wife of king Cepheus, mother of Andromeda. When Cassiopeia objected to the wedding of Perseus and Andromeda, Perseus displayed the head of Medusa, which he had concealed in his travel bag. As a result, his enemies, including Cassiopeia, were turned into stone. Neptune placed Cassiopeia in the heavens, but in order to humiliate her, he arranged it so that at certain times of the years she would appear to be hanging upside down. For the story of Andromeda and Perseus, see the film "Clash of the Titans."


Trace an imaginary line from the Big Bear's pointers on past Polaris. At an equal distance on the opposite side from the Big Dipper is Cassiopeia (KASS-ee-oh-PEE-uh), an ancient Queen of Ethiopia.

As she sits on her W-shaped throne she circles round and round the pole. Like the Big Dipper, Cassiopeia is circumpolar and therefore visible no matter what the season or time of night. In the fall Cassiopeia is in the shape of a W and in the Spring she is in the shape of a M.

[star chart]

Star chart created with Voyager II Software for Macintosh, published by Carina Software. This is just a taste of what Voyager can do! For info on Voyager II software, call Carina Software at (510) 355-1266, write them at 12919 Alcosta Blvd Suite #7, San Ramon, CA 94583, or visit Carina Software's home page and check out Voyager II for yourself.

Special Stars

In 1572 a star in Cassiopeia that previously was too faint to see flared up as bright as Venus, remaining for about a year and a half, first white and then reddish in color, before fading away. Observed by many at the time, even in daylight, it has become known as Tycho's (TEE-koze) nova, after the Danish astronomer and alchemist Tycho Brahe (BRA-hee), arguably the foremost astronomer of that generation. Tycho's Star is one of only four supernovae ever observed in the Milky Way galaxy.

Table of 25 Brightest Stars.
What is apparent stellar magnitude?

Star Clusters

M52 (Galactic cluster), mag. 8.2.

M103 (Galactic cluster), mag. 6.9.

What are Star Clusters?

Discussed in these Shows

[Small Logo] ©1997 Welcome to the Basic Celestial Phenomena web site. To provide explanations of basic observational astronomy to students, teachers, families, and visitors to planetariums these pages have been written by an ex-OBU Planetarium Director, Kerry Magruder; the OBU Natural Sciences Coordinator, Mike Keas; and some of the students who work in the OBU planetarium.

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