Lambda Doradus

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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[edit]

  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.