Epsilon Capricorni

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**ε Capricorni A/B**
Observation data Epoch J2000.0
Constellation	Capricornus
Right ascension	21^h37^m04.8^s
Declination	−19°27′58″
Apparent magnitude (V)	+4.51/+9.5
Distance	660 ± 120 ly (203 ± 38 pc)
Spectral type	B2.5Vpe/K1III-IV
Other designations
Kastra, 39 Capricorni, HR 8260, HD 205637, BD−20°6251/BD−20°6253, FK5 3724, HIP 106723, SAO 164520, GC 30252, BDS 11077, CCDM J21371-1928

Epsilon Capricorni (ε Cap / ε Capricorni) is a triple star system in the constellation Capricornus. It also has the traditional star name Kastra. It is approximately 660 light years from Earth.

The primary component, ε Capricorni A, is a blue-white B-type main sequence dwarf with a mean apparent magnitude of +4.51. It is classified as a Gamma Cassiopeiae type variable star and its brightness varies from magnitude +4.48 to +4.72. It is a spectroscopic binary, and the two subcomponents have apparent magnitudes of +5.0 and +6.3 and are separated by 0.0047 arcseconds (1 AU).

Further out, 68 arcseconds away, is ε Capricorni B which is at least 13,000 AU, or 0.22 light years away from the close binary. It is an orange K-type giant with an apparent magnitude of +9.5.