2 Vulpeculae

2 Vulpeculae
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vulpecula
2 Vul A
Right ascension 19h 17m 43.6354s[1]
Declination +23° 01′ 31.9418″[1]
Apparent magnitude (V) 5.43[2]
2 Vul B
Right ascension 19h 17m 43.7343s[3]
Declination +23° 01′ 30.8604″[3]
Characteristics
Spectral type B1 IV[4]
B−V color index 0.020±0.003[2]
Variable type β Cep[5]
Astrometry
2 Vul A
Radial velocity (Rv)+1.0±4.2[2] km/s
Proper motion (μ) RA: +0.956±0.041[1] mas/yr
Dec.: −6.636±0.087[1] mas/yr
Parallax (π)1.8212 ± 0.0880 mas[1]
Distance1,790 ± 90 ly
(550 ± 30 pc)
Absolute magnitude (MV)−2.35[2]
2 Vul B
Proper motion (μ) RA: −0.170±0.038[3] mas/yr
Dec.: −5.324±0.073[3] mas/yr
Parallax (π)1.7131 ± 0.0757 mas[3]
Distance1,900 ± 80 ly
(580 ± 30 pc)
Details
Mass12.5±0.6[6] M☉
Luminosity (bolometric)21,922[7] L☉
Temperature26,850[7] K
Metallicity [Fe/H]−0.06±0.10[8] dex
Rotational velocity (v sin i)270[9] km/s
Age12.6±0.7[6] Myr
Other designations
2 Vul, ES Vul, BD+22°3648, HD 180968, HIP 94827, HR 7318, SAO 87036, WDS 19177+2302[10]
Database references
SIMBADdata

2 Vulpeculae is a binary star[11] system in the northern constellation of Vulpecula, located around 1,800 light years away[1] from the Sun. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 5.43.[2]

2 Vulpeculae is a double-lined spectroscopic binary;[11] as of 2002, the pair had an angular separation of 1.72″ along a position angle of 127.2°.[12]

The primary component of the binary is a rapidly rotating Be star[13] with a stellar classification of B1 IV.[4] It is a variable star with an amplitude of 0.06 magnitude and a period of 0.6096 days, tentatively classified as Beta Cephei variable.[5] The variability was discovered in 1959,[14] and it has been assigned the variable star designation ES Vulpeculae.[5]

  1. ^ a b c d e f Cite error: The named reference Gaia DR3 for A was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Gaia DR3 for B was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference mk was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference hohle2010 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Gáspár2016 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Abt2002 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference chini2012 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Roberts2011 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Balona1995 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference lynds was invoked but never defined (see the help page).