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Proper NameNone
Bayer DesignationKappa Piscium
Flamsteed Number8 Piscium
HR (BSC)8911
Right Ascension23h 26m 56s
Declination+1° 15' 20"
Distance161 light years
49 parsecs
MagnitudeApparent: +4.92
Absolute: +1.46
Spectral ClassA2VpSrCrSi white main sequence star
Optimum VisibilitySeptember / October

The southernmost of the ring of seven faint stars that form the Circlet, the body of the western fish of Pisces. Kappa Piscium and its Circlet formation stand directly to the south of the prominent Square of Pegasus in the sky. It is a white star, about twice the diameter of the Sun, that lies some 161 light years from the Solar System.

The prominent star to the southeast of Kappa Piscium is the yellow giant 9 Piscium. Though the two stars are separated by just nine arcminutes in the sky, this giant is actually more than twice as distant from the Sun as Kappa Piscium. Imagery provided by Aladin sky atlas

Kappa Piscium is notable as being a variable star, belonging to the class known as Alpha2 Canum Venaticorum variables. Variations in the star's intense magnetic field cause heavy metals (particularly strontium) to distribute itself unevenly on the star's surface layers, causing its luminosity to apparently vary as it rotates on its axis. This patterning means that it is possible to measure how quickly Kappa Piscium rotates: it takes some forty-eight hours to complete one rotation (that is, the star rotates nearly thirteen times faster than the Sun).

Kappa Piscium is one of the brighter members of a loosely connected group of about a hundred stars known collectively as the AB Doradus Moving Group. Thought to share a common origin about four hundred million years ago, these stars are now widely spread across the sky. Most are extremely faint as seen from Earth, but other prominent members of the same group include Rukbat in Sagittarius and Alnair in Grus.


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