The constellation Cepheus.
Click on image for full size
Windows to the Universe original image

King Cepheus

Cepheus is one of the oldest constellations in the night sky. He is a circumpolar constellation, circling around the North Star all year long. This house-shaped constellation is named after an ancient king of a land called Ethiopia (different from the current country, Ethiopia). He was married to the beautiful Cassiopeia and had a daughter, Andromeda.

In Greek mythology, Cassiopeia boasted that she and her daughter were more beautiful than the Nereids. They complained to the sea god Poseidon, who sent a monster to destroy Cepheus' land. The king and queen offered their daughter to the monster, but she was saved by Perseus. All four people, along with the monster, are represented in the sky by constellations.

Cepheus looks like a house with a steep roof. It is not clear as to what ancient people saw in this constellation. It is full of interesting objects. The brightest star in the constellation is Alderamin, which is the westernmost star in Cepheus. The top of the house is a special type of star called a cepheid. Cepheids are pulsating stars, used to find large distances.

Cepheus is full of galaxies and nebulae, although most are too dim to see with the naked eye. If you scan across the constellation with a telescope, you should find at least four different nebulae. It is also full of star clusters, ten to be exact. Unfortunately, most must be viewed with a telescope. Slightly south of Cepheus lies a star that would be considered the North Star if we lived on Mars. This red cepheid is one of the most colorful stars in the sky.

You might also be interested in:

Ready, Set, SCIENCE!: Putting Research to Work in K-8 Science Classrooms

What types of instructional experiences help K-8 students learn science with understanding? What do science educators teachers, teacher leaders, science specialists, professional development staff, curriculum designers, school administrators need to know to create and support such experiences?...more


In Greek mythology, Andromeda was the daughter of Cassiopeia and Cepheus, king of Ethiopia. Andromeda's mother claimed that they were more beautiful than the sea nymphs, the Nereids. The Nereids felt insulted...more


The constellation Cetus represents the Sea Monster. It is one of the largest constellations known. Even the ancient people of Mesopotamia recognized this large constellation. They believed the figure was...more


Perseus was an ancient Greek hero. His mother was Danae, the daughter of the king of Argos, Acrisius. When a prophecy revealed to Acrisius that his grandson would kill him, he imprisoned his daughter Danae...more


Andromeda is a "V" shaped constellation best viewed in Autumn if you live in the Northern Hemisphere. It was one of the earliest constellations to be recognized. Andromeda lies near the celestial north...more


Perseus, the Hero, can be found in the sky during the winter in the Northern Hemisphere. With a little imagination, you can see the image of a man in the stars. He has a sort of triangular body, with...more

Ursa Major

Ursa Major is probably the most famous constellation, with the exception of Orion. Also known as the Great Bear, it has a companion called Ursa Minor, or Little Bear. Everyone living in the Northern Hemisphere...more

40 Eridani B - Burnt-Out Cinder

What's in a Name: Star designated 40 in the constellation Eridanus. Claim to Fame: One of the first white dwarfs found. A white dwarf is the exposed extremely hot core of a star that has blown off its...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA