File:Cepheus_constellation_crop_VV_Cephei_location.png · Wikimedia Commons · See Wikimedia Commons
VV Cephei
Sign in to saveAlso known as HD 208816, HR 8383, VV Cep, PLX 5308, HIP 108317, HIC 108317, GCRV 13794, DO 40453
binary star in the constellation Cepheus
Key facts
- Constellation
- Cepheus
- Right ascension
- 21 56 39.14385
- Declination
- +63 ° 37 ′ 32.0174 ″
- Apparent magnitude v
- 4.91 (4.80 - 5.36 )
- U b color index
- +0.43
- B v color index
- +1.73
- Variable type
- EA + SRc
- Evolutionary stage
- Red supergiant
- Spectral type
- M2 Iab (M1p 0)
via Wikipedia infobox
~9 min read
Encyclopedic overview
VV Cephei, also known as HD 208816, is an eclipsing binary star system located in the constellation Cepheus. It is both a B[e] star and shell star. As a 5th magnitude star, it is visible to the naked eye under good observing conditions.
VV Cephei is an eclipsing binary with the third 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 galaxy although its size is not certain. Estimates range from 660 R☉ to over 1,000 R☉.
Excerpted from Wikipedia’s “VV Cephei” article, available under the CC BY-SA 4.0 licence.