VV Cephei stars
VV Cephei stars(see -fee-ÿ) A class of massive interacting binary stars, with orbital periods from somewhat less than a year to several decades, in which a massive supergiant (usually an M star) transfers mass to a blue companion (typically a B star). The mass donor appears to fill or almost fill its Roche lobe (see equipotential surfaces). Because most VV Cephei stars have very eccentric orbits, mass transfer often appears to be strongest near the phase of closest approach. VV Cephei systems are the more evolved counterparts of Zeta Aurigae systems. Some well-studied examples include VV Cephei, AZ Cassiopeiae, and KQ Puppis.
VV Cephei stars[¦vē¦vē ′sef·ē‚ī ‚stärz]
A class of long-period eclipsing binary stars, with M supergiant primaries, a blue (usually B) supergiant or giant secondaries, and small variations in light.