WhatTheStar

Constellations · Constellation · Cephei · Cep

Constellation

Cepheus

King Cepheus, husband of Cassiopeia — shaped like a child’s drawing of a house. One of its stars became a ruler for the universe.

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Genitive
Cephei
Area
588 square degrees · 27th of 88
Brightest star
Alderamin · magnitude 2.45
Naked-eye stars
158 brighter than magnitude 6.5
Highest at midnight
late August

Discovery

Delta Cephei brightens and fades every 5.4 days. John Goodricke noticed in 1784; Henrietta Leavitt later found that stars like it — Cepheids — reveal their true brightness, and so their distance.

Look for

Herschel’s Garnet Star is one of the reddest stars you can see with the naked eye, a supergiant larger than Betelgeuse.

Did you know

Errai will be the pole star in about 1,000 years, as precession swings the pole away from Polaris.

Words used here

All constellations · Field guide · Open the sky map

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