Astronomy:WZ Doradus

From HandWiki
Short description: Semiregular variable in Dorado
WZ Doradus
Dorado constellation map.svg
Red circle.svg
Location of WZ Doradus on the map (circled)
Observation data
Epoch J2000.0   Equinox (celestial coordinates)
Constellation Dorado
Right ascension  05h 07m 34.02686s[1]
Declination −63° 23′ 58.8474″[1]
Apparent magnitude (V) 5.20 - 5.32[2]
Characteristics
Evolutionary stage AGB[3]
Spectral type M3 III[4]
U−B color index +1.85[5]
B−V color index +1.65[5]
Variable type SRb[2]
Astrometry
Radial velocity (Rv)19.3±2.8[6] km/s
Proper motion (μ) RA: +13.210[1] mas/yr
Dec.: −44.813[1] mas/yr
Parallax (π)5.6282 ± 0.1116[1] mas
Distance580 ± 10 ly
(178 ± 4 pc)
Absolute magnitude (MV)−1.00[7]
Details
Mass1.4[8] M☉
Radius88.3+6.6−10.0[9] R☉
Luminosity1,248±47[9] L☉
Surface gravity (log g)0.50[10] cgs
Temperature3,603±125[10] K
Other designations
WZ Dor, CD−63°188, CPD−63°420, FK5 2389, GC 6314, HD 33684, HIP 23840, HR 1695, SAO 249198[11]
Database references
SIMBADdata

WZ Doradus (HD 33684; HR 1695; 21 G. Doradus) is a solitary red-hued variable star[12] located in the southern constellation Dorado. It has an average apparent magnitude of 5.21,[13] making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of 580 light-years[1] and it is currently receding with a heliocentric radial velocity of 19.3 km/s.[6] At its current distance, WZ Doradus is diminished by two-tenths of a magnitude due to interstellar extinction and it has an absolute magnitude of −1.00.[7]

HD 33684 was first observed to vary in brightness by astronomer P. M. Corben in 1971.[14] It was said to have an amplitude of 0.18 magnitudes. A year later, HD 33684 was given the variable star designation WZ Doradus.[15] It was again observed in 1973 by Olin J. Eggen and he noticed that it varied within 40 days.[16] A 1998 survey found no strong emissions indicating dust around the star.[17] Another survey also found no technetium in its spectrum.[18] WZ Doradus is a semiregular variable of subtype SRb that varies between 5.2 and 5.32 within an average period of 40 days.[2] Tabur et al. (2009) found two periods for the star after it was widely believed to only have one period.[19]

WZ Doradus variability periods[19]
Amplitude (mag) Period (days)
0.042 26.0
0.026 44.6

WZ Doradus has a stellar classification of M3 III,[4] indicating that it is an evolved red giant. It is currently on the asymptotic giant branch,[3] generating energy via the fusion of hydrogen and helium shells around an inert carbon core. As a result of its evolved state, it has expanded to 88.3 times the radius of the Sun[9] and it now radiates 1,248 times the luminosity of the Sun[9] from its enlarged photosphere at an effective temperature of 3,603 K.[10]

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. ↑ 2.0 2.1 2.2 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. doi:10.1134/S1063772917010085. ISSN 1063-7729. Bibcode: 2017ARep...61...80S. 
  3. ↑ 3.0 3.1 Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun". The Astronomical Journal 104: 275. doi:10.1086/116239. ISSN 0004-6256. Bibcode: 1992AJ....104..275E. 
  4. ↑ 4.0 4.1 Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars: Declinations −90° to −53°. 1. Bibcode: 1975mcts.book.....H. 
  5. ↑ 5.0 5.1 Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data. SIMBAD, Bibcode: 1986EgUBV........0M 
  6. ↑ 6.0 6.1 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. doi:10.1134/S1063773706110065. ISSN 1063-7737. Bibcode: 2006AstL...32..759G. 
  7. ↑ 7.0 7.1 Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode: 2012AstL...38..331A. 
  8. ↑ Kervella, Pierre et al. (March 2019). "Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly". Astronomy & Astrophysics 623: 23. doi:10.1051/0004-6361/201834371. A72. Bibcode: 2019A&A...623A..72K. 
  9. ↑ 9.0 9.1 9.2 9.3 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  10. ↑ 10.0 10.1 10.2 McDonald, I.; Zijlstra, A. A.; Watson, R. A. (15 June 2017). "Fundamental parameters and infrared excesses of Tycho–Gaia stars". Monthly Notices of the Royal Astronomical Society 471 (1): 770–791. doi:10.1093/mnras/stx1433. ISSN 0035-8711. Bibcode: 2017MNRAS.471..770M. 
  11. ↑ "V* WZ Dor". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=V%2A+WZ+Dor. 
  12. ↑ Eggleton, P. P.; Tokovinin, A. A. (11 September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society 389 (2): 869–879. doi:10.1111/j.1365-2966.2008.13596.x. ISSN 0035-8711. Bibcode: 2008MNRAS.389..869E. 
  13. ↑ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P. et al. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics 355: L27–L30. ISSN 0004-6361. Bibcode: 2000A&A...355L..27H. 
  14. ↑ Corben, P. M. (April 1971). "Photoelectric Magnitudes and Colours for Bright Southern Stars". Monthly Notes of the Astronomical Society of South Africa 30 (4): 37. ISSN 0024-8266. Bibcode: 1971MNSSA..30...37C. 
  15. ↑ Kukarkin, B. V.; Kholopov, P. N.; Kukarkina, N. P.; Perova, N. B. (1 September 1972). "58th Name-List of Variable Stars". Information Bulletin on Variable Stars 717: 1. ISSN 0374-0676. Bibcode: 1972IBVS..717....1K. 
  16. ↑ Eggen, O. J. (September 1973). "The classification of intrinsic variables. IV. Very-small-amplitude, very-short-period red variables". The Astrophysical Journal 184: 793. doi:10.1086/152371. ISSN 0004-637X. Bibcode: 1973ApJ...184..793E. 
  17. ↑ Sloan, G. C.; Price, S. D. (December 1998). "The Infrared Spectral Classification of Oxygen‐rich Dust Shells". The Astrophysical Journal Supplement Series (American Astronomical Society) 119 (2): 141–158. doi:10.1086/313156. ISSN 0067-0049. Bibcode: 1998ApJS..119..141S. 
  18. ↑ Lebzelter, Th.; Hron, J. (November 1999). "A search for Technetium in semiregular variables". Astronomy and Astrophysics 351: 533–542. ISSN 0004-6361. Bibcode: 1999A&A...351..533L. 
  19. ↑ 19.0 19.1 Tabur, V.; Bedding, T. R.; Kiss, L. L.; Moon, T. T.; Szeidl, B.; Kjeldsen, H. (21 December 2009). "Long-term photometry and periods for 261 nearby pulsating M giants". Monthly Notices of the Royal Astronomical Society 400 (4): 1945–1961. doi:10.1111/j.1365-2966.2009.15588.x. ISSN 0035-8711. Bibcode: 2009MNRAS.400.1945T. 
Cite error: <ref> tag with name "Gould1879" defined in <references> is not used in prior text.



Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:WZ_Doradus&oldid=3425053"