Epsilon Ursae Minoris

Epsilon Ursae Minoris (ε UMi, ε Ursae Minoris) is a triple star system in the constellation Ursa Minor. It is approximately 303 light years from Earth.

The primary component, Epsilon Ursae Minoris A, is an eclipsing spectroscopic binary. It is classified as a yellow G-type giant with a mean apparent magnitude of +4.21. In addition to light changes due to eclipses, the system is also classified as an RS Canum Venaticorum type variable star and its brightness varies from magnitude +4.19 to +4.23 with a period of 39.48 days, which is also the orbital period of the binary. The binary is orbited by a third component, Epsilon Ursae Minoris B, which is an 11th magnitude star, 77 arcseconds away in the sky.