20 Vulpeculae

20 Vulpeculae
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vulpecula
Right ascension 20h 12m 00.70176s[1]
Declination +26° 28′ 43.6989″[1]
Apparent magnitude (V) 5.91[2]
Characteristics
Evolutionary stage main sequence[3]
Spectral type B7 Ve[4][5]
B−V color index −0.107±0.003[2]
Astrometry
Radial velocity (Rv)−22.0±4.3[2] km/s
Proper motion (μ) RA: +4.096[1] mas/yr
Dec.: −9.524[1] mas/yr
Parallax (π)2.7904 ± 0.0726 mas[1]
Distance1,170 ± 30 ly
(358 ± 9 pc)
Absolute magnitude (MV)−2.13[2]
Details
Mass4.02±0.14[3] M☉
Radius3.0[6] R☉
Luminosity460+88
−74[3] L☉
Surface gravity (log g)2.90[7] cgs
Temperature12,050+168
−165[3] K
Rotational velocity (v sin i)236[3] km/s
Other designations
20 Vul, BD+26°3828, HD 192044, HIP 99531, HR 7719, SAO 88339[8]
Database references
SIMBADdata

20 Vulpeculae is single[5] star located around 1,170[1] light years away in the northern constellation of Vulpecula.[8] It is visible to the naked eye as a dim, blue-white hued star with an apparent visual magnitude of 5.91.[2] The object is moving closer to the Earth with a heliocentric radial velocity of −22 km/s.[2]

This is a Be star with a stellar classification of B7 Ve.[4] It is spinning rapidly with a projected rotational velocity of 236 km/s (compared to a critical velocity of 332 km/s)[3] and has an estimated polar inclination of 71.1°.[9] 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.[3]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c d e f g Cite error: The named reference zorec2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Antoniou2011 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Fracassini2001 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Chauville2001 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Simbad was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Frémat2005 was invoked but never defined (see the help page).