extrinsic variable

An extrinsic variable is a variable star, the light fluctuations of which are not due to changes in the star itself but to an external effect such as eclipses, obscuration, rotation, or tidal distortion. The main categories are eclipsing binary, which includes Algol stars, Beta Lyrae stars, and W Ursae Majoris stars, and rotating variable, which includes Alpha2 Canum Venaticorum star, BY Draconis star, ellipsoidal variable, FK Comae Berenices star, and SX Arietis star.


Compare with intrinsic variable.