Jump to content

V692 Coronae Australis

From Wikipedia, the free encyclopedia
V692 Coronae Australis
Location of V692 CrA (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Corona Australis
Right ascension 18h 13m 12.69843s[1]
Declination −41° 20′ 09.9972″[1]
Apparent magnitude (V) 5.46[2] (5.46 - 5.51)[3]
Characteristics
Spectral type B2 III[4] or B1.5 IIIp[5]
B−V color index −0.17[6]
Variable type SX Arietis[7]
Astrometry
Radial velocity (Rv)−15.3±2.8[8] km/s
Proper motion (μ) RA: −2.050 mas/yr[1]
Dec.: −6.210 mas/yr[1]
Parallax (π)1.7423 ± 0.0977 mas[1]
Distance1,900 ± 100 ly
(570 ± 30 pc)
Absolute magnitude (MV)−6.44[9] or −2.26[10]
Details
Mass7.35±0.48[11] M☉
Radius12.6±0.7[12] R☉
Luminosity (bolometric)4,181[11] L☉
Surface gravity (log g)3.52+0.33
−0.14[1] cgs
Temperature17,061+1,474
−1,357[13] K
Rotational velocity (v sin i)212±9[14] km/s
Age31.6±5.1[15] Myr
Other designations
3 G. Corona Australis[16], V692 CrA, CD−41°12534, CPD−41°8620, GC 24824, HD 166596, HIP 89290, HR 6804, SAO 228815[17]
Database references
SIMBADdata

V692 Coronae Australis (HD 166596; HR 6804; 3 G. CrA), or simply V692 CrA, is a whitish-blue hued variable star located in the southern constellation Corona Australis. It has a maximum apparent magnitude of 5.46,[2] making it faintly visible to the naked eye. The object is located relatively far at a distance of approximately 1,900 light years based on Gaia DR3 parallax measurements,[1] but it is approaching the Solar System with a fairly constrained heliocentric radial velocity of −15.3 km/s.[8] At its current distance, V692 CrA's brightness is heavily diminished by 0.46 magnitudes due to extinction due to interstellar dust.[18] Its absolute magnitude depends on the source: Westin (1985) gave a value of −6.44[9] while the extended Hipparcos catalogue gave a value of −2.26.[10]

A light curve for V692 Coronae Australis, plotted from Hipparcos data[19]

Astronomers Carlos and Mercedes Jaschek along with a colleague listed HD 166596 as a Be star in 1964.[20] However, its status as an Ap star was not observed until 1979 by astronomers N. Vogt and A.M Faundez.[21] A year later, HD 166596 was observed to be variable and it had a period of 1.67 days.[22] In 1981, its variability was confirmed and it was given the variable star designation V692 Coronae Australis—the 692nd variable star in Corona Australis.[23] The star might have a shorter period of 49.8 hours.[7]

V692 CrA has a stellar classification of B2 III[4] or B1.5 IIIp,[5] both indicating that it is a slightly evolved B-type giant star. The second classification indicates that V692 CrA has peculiarities in its spectrum. It has 7.35 times the mass of the Sun[11] and 12.6 times the Sun's radius.[12] It radiates at a bolometric luminosity 4,181 times that of the Sun[11] from its photosphere at an effective temperature of 17,061 K.[13] V692 CrA is estimated to be 31.6 million years old[15] and it spins rapidly with a projected rotational velocity of 212 km/s.[14]

References

[edit]
  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 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361. S2CID 17128864.
  3. ^ "VSX : Detail for V0692 CrA". www.aavso.org.
  4. ^ a b Houk, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars: Declinations −53° to −40°. Vol. 2. Bibcode:1978mcts.book.....H.
  5. ^ a b Rountree, Janet; Sonneborn, George (March 1991). "Criteria for the spectral classification of B stars in the ultraviolet". The Astrophysical Journal. 369: 515. Bibcode:1991ApJ...369..515R. doi:10.1086/169781. eISSN 1538-4357. ISSN 0004-637X. S2CID 118640556.
  6. ^ Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J. S2CID 118307502.
  7. ^ a b Samus’, N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (January 2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. eISSN 1562-6881. ISSN 1063-7729. S2CID 125853869.
  8. ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
  9. ^ a b Westin, T. N. G. (April 1985). "The local system of early type stars. Spatial extent and kinematics". Astronomy and Astrophysics Supplement Series. 60: 99–134. Bibcode:1985A&AS...60...99W. ISSN 0365-0138. S2CID 119020376.
  10. ^ a b Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
  11. ^ a b c d Hohle, M.M.; Neuhäuser, R.; Schutz, B.F. (April 2010). "Masses and luminosities of O- and B-type stars and red supergiants". Astronomische Nachrichten. 331 (4): 349–360. arXiv:1003.2335. Bibcode:2010AN....331..349H. doi:10.1002/asna.200911355. eISSN 1521-3994. ISSN 0004-6337. S2CID 111387483.
  12. ^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants. Surface brightness relations calibrated by interferometry". Astronomy & Astrophysics. 426 (1): 297–307. arXiv:astro-ph/0404180. Bibcode:2004A&A...426..297K. doi:10.1051/0004-6361:20035930. eISSN 1432-0746. ISSN 0004-6361. S2CID 6077801.
  13. ^ a b Gulati, R. K.; Malagnini, M. L.; Morossi, C. (October 1989). "Empirical temperature calibrations for early-type stars". Astronomy and Astrophysics Supplement Series. 80: 73–88. Bibcode:1989A&AS...80...73G. ISSN 0365-0138. S2CID 115777506.
  14. ^ a b Brown, A. G. A.; Verschueren, W. (March 1997). "High S/N Echelle spectroscopy in young stellar groups. II. Rotational velocities of early-type stars in SCO OB2". Astronomy & Astrophysics. 319: 811–838. arXiv:astro-ph/9608089. Bibcode:1997A&A...319..811B. ISSN 0004-6361. S2CID 118925453.
  15. ^ a b Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (October 12, 2010). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1). Oxford University Press (OUP): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. ISSN 0035-8711. S2CID 118629873.
  16. ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
  17. ^ "V* V692 CrA". SIMBAD. Centre de données astronomiques de Strasbourg.
  18. ^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711. S2CID 118879856.
  19. ^ EAS (1997). "The HIPPARCOS and TYCHO catalogues". Astrometric and Photometric Star Catalogues Derived from the ESA Hipparcos Space Astrometry Mission. ESA SP Series. 1200. Noordwijk, Netherlands: ESA Publications Division. Bibcode:1997HIP...C......0E. ISBN 9290923997. Retrieved 15 October 2022.
  20. ^ Jaschek, C.; Jaschek, M.; Kucewicz, B. (1964). "A Survey of Southern Be Stars". Zeitschrift für Astrophysik. 59: 108. Bibcode:1964ZA.....59..108J. ISSN 0372-8331. S2CID 117724232.
  21. ^ Vogt, N.; Faundez, A. M. (1 June 1979). "Photoelectric observations of peculiar A and related stars I: Strömgren photometry of 341 Ap stars". Astronomy and Astrophysics Supplement Series. 36: 477–484. Bibcode:1979A&AS...36..477V. ISSN 0365-0138.
  22. ^ Renson, P.; Manfroid, J. (March 1980). "Nouvelle Recherche de Periodes d'etoiles Ap Observees a l'ESO-IV". Information Bulletin on Variable Stars. 1755: 1. Bibcode:1980IBVS.1755....1R. ISSN 0374-0676.
  23. ^ Kholopov, P. N.; Samus', N. N.; Kukarkina, N. P.; Medvedeva, G. I.; Perova, N. B. (November 1981). "66th Name-List of Variable Stars". Information Bulletin on Variable Stars. 2042: 1. Bibcode:1981IBVS.2042....1K. ISSN 0374-0676.
Retrieved from "https://en.wikipedia.org/w/index.php?title=V692_Coronae_Australis&oldid=1171018352"