3 Vulpeculae

3 Vulpeculae
Location of 3 Vulpeculae (circled in red)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vulpecula
Right ascension 19h 22m 50.8856s[1]
Declination +26° 15′ 44.667″[1]
Apparent magnitude (V) 5.18[2]
Characteristics
Evolutionary stage main sequence[1]
Spectral type B7V[3]
B−V color index −0.119±0.001[2]
Variable type SPB[4][5]
Astrometry
Radial velocity (Rv)−14.1±1.1[2] km/s
Proper motion (μ) RA: 0.922(124) mas/yr[1]
Dec.: −10.270(163) mas/yr[1]
Parallax (π)8.9071±0.1685 mas[1]
Distance366 ± 7 ly
(112 ± 2 pc)
Absolute magnitude (MV)−0.17[2]
Orbit[4]
Period (P)367.7 days
Eccentricity (e)0.15
Semi-amplitude (K1)
(primary)
6.8 km/s
Details
A
Mass4.16[4] M
Luminosity286+64
−52
[6] L
Surface gravity (log g)4.30[4] cgs
Temperature14,343[4] K
Rotational velocity (v sin i)15.5[7] km/s
B
Mass0.6 - 1.1[4] M
Age25[4] Myr
Other designations
3 Vul, V377 Vulpeculae, BD+25°3811, GC 26748, HD 182255, HIP 95260, HR 7358, SAO 87136[8]
Database references
SIMBADdata

3 Vulpeculae (abbreviated 3 Vul) is a binary star system in the northern constellation of Vulpecula,[8] located around 366 light years away from the Sun.[1] 3 Vulpeculae is its Flamsteed designation. It is visible to the naked eye as a faint, blue-white hued star with a baseline apparent visual magnitude of 5.18.[2]

In 1991 Douglas Hube and Christopher Aikman announced their discovery that 3 Vul's brightness varies.[10] The star has been nicknamed "the Observer's Nightmare" (or its Latin free translation, "Spectatori Error Inextricabilis") by some astronomers[11][4] because it is difficult to study as its orbital period is close to a year, and additionally it is pulsating with a period close to a day.[4] From a twenty-year spectroscopic study, Hube and Aikman established a 367-day orbital period, and noted the presence of non-radial pulsations in the primary star. From sparse photometry, the authors also established the star's light variability. They suggested that the primary is a member of the 53 Persei class of variable stars.[10] Such stars are now collectively known by the term slowly pulsating B-type stars. Its photometric variation led to a variable star designation, as V377 Vulpeculae, but the non-reproducibility of the light curve made determination of the pulsation period elusive.

Continuous monitoring of the star by the Transiting Exoplanet Survey Satellite has revealed a beat-period phenomenon in the light curve, which causes the luminosity variations to fluctuate in amplitude. The pulsations are non-radial, that is, the star's photosphere varies in shape rather than volume; different parts of the star are expanding and contracting simultaneously. These gravity waves, or g-mode waves, can be indicative of the interior structure of the star.[12]

The primary member, designated component A, is a most likely a B-type main-sequence star[6] with a stellar classification of B7V.[3] The star has 4.16[4] times the mass of the Sun and is radiating 286[6] times the Sun's luminosity from its photosphere at an effective temperature of 14,343 K.[4] The secondary has an estimated 0.6–1.1 solar masses.[4]

References

  1. ^ a b c d e f Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c d e Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
  3. ^ a b Negueruela, I.; Simón-Díaz, S.; De Burgos, A.; Casasbuenas, A.; Beck, P. G. (2024). "The IACOB project: XII. New grid of northern standards for the spectral classification of B-type stars". Astronomy and Astrophysics. 690. arXiv:2407.04163. Bibcode:2024A&A...690A.176N. doi:10.1051/0004-6361/202449298.
  4. ^ a b c d e f g h i j k l Dukes, Robert; Kubinec, William; Kubinec, Angela; Adelman, Saul (2003). "A Photometric and Spectroscopic Study of 3 Vulpeculae: An Observer's Nightmare". The Astronomical Journal. 126 (1): 370. Bibcode:2003AJ....126..370D. doi:10.1086/375463.
  5. ^ Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
  6. ^ a b c Walczak, P.; et al. (December 2012). "Constraints on stellar parameters of the slowly pulsating B star HD 182255 from complex asteroseismology". Astronomische Nachrichten. 333 (10): 1065. arXiv:1212.4643. Bibcode:2012AN....333.1065W. doi:10.1002/asna.201211824. S2CID 116926922.
  7. ^ Zverko, J.; Romanyuk, I.; Iliev, I.; Kudryavtsev, D.; Stateva, I.; Semenko, E. (April 2016). "Stars with discrepant v sin i as derived from the Ca II λ3933 Å and Mg II λ4481 Å lines. V. HD 182255 and HD 214923—SPB stars in binary systems". Astrophysical Bulletin. 71 (2): 199–207. Bibcode:2016AstBu..71..199Z. doi:10.1134/S1990341316020073. S2CID 124871780.
  8. ^ a b "3 Vul". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-13.
  9. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  10. ^ a b Hube, Douglas P.; Aikman, G. C. L. (1991). "3 Vulpeculae: A non-radial pulsator in a one-year binary system". Publications of the Astronomical Society of the Pacific. 103 (659): 49–62. Bibcode:1991PASP..103...49H. doi:10.1086/132794.
  11. ^ Kaler, Jim. "3 Vul". Retrieved 2016-08-09.
  12. ^ Triana, S. A.; Moravveji, E.; Pápics, P. I.; Aerts, C.; Kawaler, S. D.; Christensen-Dalsgaard, J. (September 2015). "The Internal Rotation Profile of the B-type Star KIC 10526294 from Frequency Inversion of its Dipole Gravity Modes". The Astrophysical Journal. 810 (1). arXiv:1507.04574. Bibcode:2015ApJ...810...16T. doi:10.1088/0004-637X/810/1/16.