20 Vulpeculae

20 Vulpeculae
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vulpecula
Right ascension 20h 12m 00.70176s
Declination +26° 28 43.6989
Apparent magnitude (V) 5.91
Characteristics
Evolutionary stage main sequence
Spectral type B7 Ve
B−V color index −0.107±0.003
Astrometry
Radial velocity (Rv)−22.0±4.3 km/s
Proper motion (μ) RA: +4.096 mas/yr
Dec.: −9.524 mas/yr
Parallax (π)2.7904±0.0726 mas
Distance1,170 ± 30 ly
(358 ± 9 pc)
Absolute magnitude (MV)−2.13
Details
Mass4.02±0.14 M
Radius3.0 R
Luminosity460+88
−74
 L
Surface gravity (log g)2.90 cgs
Temperature12,050+168
−165
 K
Rotational velocity (v sin i)236 km/s
Other designations
20 Vul, BD+26°3828, HD 192044, HIP 99531, HR 7719, SAO 88339
Database references
SIMBADdata

20 Vulpeculae is single star located around 1,170 light years away in the northern constellation of Vulpecula. It is visible to the naked eye as a dim, blue-white hued star with an apparent visual magnitude of 5.91. The object is moving closer to the Earth with a heliocentric radial velocity of −22 km/s.

This is a Be star with a stellar classification of B7 Ve. It is spinning rapidly with a projected rotational velocity of 236 km/s (compared to a critical velocity of 332 km/s) and has an estimated polar inclination of 71.1°. The star has four times the mass of the Sun and is radiating around 460 times the Sun's luminosity from its photosphere at an effective temperature of 12,050 K.