VV Cephei

VV Cephei, also known as HD 208816, is an eclipsing binary star system located in the Constellation Cepheus, approximately 5,000 light years from Earth. It is both a B[e] star and shell star.
VV Cephei is an eclipsing binary with the second longest known period. A Red Supergiant fills its Roche lobe when closest to a companion blue star, the latter appearing to be on the main sequence. Matter flows from the red supergiant onto the blue companion for at least part of the orbit and the hot star is obscured by a large disk of material. The supergiant primary, known as VV Cephei A, is currently recognised as one of the largest stars in the Milky Way although its size is not certain. It varies from 1,600 to 1,900 solar diameters. If placed in our solar system, VV Cephei A's Photosphere would extend past the orbit of Jupiter and approach that of Saturn.
Category:Cosmology