Jump to content

Lambda Doradus

From Wikipedia, the free encyclopedia
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.
λ Doradus
Location of λ Doradus on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Dorado
Right ascension 05h 26m 19.26577s[1]
Declination −58° 54′ 45.06402″[1]
Apparent magnitude (V) 5.13±0.01[2]
Characteristics
Evolutionary stage red giant branch[3]
Spectral type G6 III[4] or G8 III[5]
B−V color index +1.00[6]
Astrometry
Radial velocity (Rv)10±0.07[7] km/s
Proper motion (μ) RA: −9.792 mas/yr[1]
Dec.: +33.350 mas/yr[1]
Parallax (π)5.9209 ± 0.0712 mas[1]
Distance551 ± 7 ly
(169 ± 2 pc)
Absolute magnitude (MV)−0.6[8]
Details[9]
Mass3.82±0.16 M
Radius21.1±0.5 R
Luminosity252±L
Surface gravity (log g)2.41±0.12 cgs
Temperature5,009±43 K
Metallicity [Fe/H]−0.06±0.04 dex
Rotational velocity (v sin i)5.2±1[10] km/s
Age258[11] Myr
Other designations
λ Dor, 23 G. Doradus[12], CPD−59°472, FK5 2410, GC 6749, HD 36189, HIP 25429, HR 1836, SAO 233981[13]
Database references
SIMBADdata

Lambda Doradus (Lambda Dor), Latinized from λ Doradus, is a solitary[14] yellow hued star located in the southern constellation Dorado. It has an apparent magnitude of 5.13,[2] making it faintly visible to the naked eye if viewed under ideal conditions. Parallax measurements place the star at a distance of 551 light years,[1] and it is currently receding with a heliocentric radial velocity of 10 km/s.[7]

Lambda Dor has a stellar classification of either G6[4] or G8 III,[5] depending on the source. Nevertheless, both indicate that it is a red giant, and it is currently on the red giant branch fusing hydrogen in a shell outside a helium core.[3] At present it has 3.82 times the mass of the Sun[9] and at an age of 258 million years, it has expanded to a radius of 21.2 R.[9] It radiates at over 250 times the luminosity of the Sun from its photosphere at an effective temperature of 5,009 K.[9] Lambda Dor is slightly metal deficient, with an iron abundance 12% below solar levels.[9] It currently spins with a projected rotational velocity of 5.2 km/s.[10]

References

  1. ^ a b c d e 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.
  3. ^ a b Setiawan, J.; Pasquini, L.; da Silva, L.; von der Lühe, O.; Hatzes, A. (January 2003). "Precise radial velocity measurements of G and K giants". Astronomy & Astrophysics. 397 (3): 1151–1159. Bibcode:2003A&A...397.1151S. doi:10.1051/0004-6361:20021559. eISSN 1432-0746. ISSN 0004-6361.
  4. ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations −90° to −53°. Bibcode:1975mcts.book.....H.
  5. ^ a b Keenan, Philip C.; McNeil, Raymond C. (October 1989). "The Perkins catalog of revised MK types for the cooler stars". The Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373. eISSN 1538-4365. ISSN 0067-0049.
  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.
  7. ^ a b Jofré, E.; Petrucci, R.; Saffe, C.; Saker, L.; Artur de la Villarmois, E.; Chavero, C.; Gómez, M.; Mauas, P. J. D. (26 January 2015). "Stellar parameters and chemical abundances of 223 evolved stars with and without planets". Astronomy & Astrophysics. 574: A50. arXiv:1410.6422. Bibcode:2015A&A...574A..50J. doi:10.1051/0004-6361/201424474. eISSN 1432-0746. ISSN 0004-6361.
  8. ^ 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.
  9. ^ a b c d e Ottoni, G.; Udry, S.; Ségransan, D.; Buldgen, G.; Lovis, C.; Eggenberger, P.; Pezzotti, C.; Adibekyan, V.; Marmier, M.; Mayor, M.; Santos, N. C.; Sousa, S. G.; Lagarde, N.; Charbonnel, C. (January 2022). "CORALIE radial-velocity search for companions around evolved stars (CASCADES): I. Sample definition and first results: Three new planets orbiting giant stars". Astronomy & Astrophysics. 657: A87. arXiv:2201.01528. Bibcode:2022A&A...657A..87O. doi:10.1051/0004-6361/202040078. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. eISSN 1432-0746. ISSN 0004-6361.
  11. ^ Gomes da Silva, J.; Santos, N. C.; Adibekyan, V.; Sousa, S. G.; Campante, T. L.; Figueira, P.; Bossini, D.; Delgado-Mena, E.; Monteiro, M. J. P. F. G.; de Laverny, P.; Recio-Blanco, A.; Lovis, C. (February 2021). "Stellar chromospheric activity of 1674 FGK stars from the AMBRE-HARPS sample". Astronomy & Astrophysics. 646: A77. arXiv:2012.10199. Bibcode:2021A&A...646A..77G. doi:10.1051/0004-6361/202039765. eISSN 1432-0746. ISSN 0004-6361.
  12. ^ 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.
  13. ^ "lam Dor". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved August 21, 2022.
  14. ^ 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. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. eISSN 1365-2966. ISSN 0035-8711.