Delta Trianguli Australis Luminous G-type star; Triangulum Australe
Delta Trianguli Australis (Delta TrA), Latinized from δ Trianguli Australis , is a solitary,[ 14] yellow-hued star in the constellation Triangulum Australe . It has an apparent magnitude of 3.84,[ 2] making it readily visible to the naked eye under ideal conditions, Parallax measurements place the object at a distance of 606 light years (182 parsecs).[ 1] It has a heliocentric radial velocity of −4.9 km/s ,[ 5] indicating that it is drifting towards the Solar System .
Delta TrA has a stellar classification of G2 Ib-IIa[ 3] — an evolved G-type star with a luminosity class intermediate between a low luminosity supergiant and a bright giant . At present it has 6.5 times the mass of the Sun [ 7] and has an enlarged radius of 53.6 R ☉ .[ 8] It radiates at 1,210 times the luminosity of the Sun [ 9] from its photosphere at an effective temperature of 4,705 K .[ 8] Delta TrA has an iron abundance 89% that of the Sun ,[ 10] placing it around solar metallicity . It spins modestly with a projected rotational velocity of 8.2 km/s , which is high for stars of this type.[ 11]
References
^ a b c d e van Leeuwen, Floor (13 August 2007). "Validation of the new Hipparcos reduction" . Astronomy & Astrophysics . 474 (2): 653– 664. arXiv :0708.1752 . Bibcode :2007A&A...474..653V . doi :10.1051/0004-6361:20078357 . eISSN 1432-0746 . ISSN 0004-6361 . Hipparcos record for this source at VizieR .
^ 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 .
^ 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 .
^ a b Cousins, A. W. J. (1971). "Photometric standard stars". Royal Observatory Annals . 7 . Bibcode :1971ROAn....7.....C .
^ 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 .
^ 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 .
^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (20 December 2021). "Stellar and substellar companions from Gaia EDR3" . Astronomy & Astrophysics . 657 : A7. arXiv :2109.10912 . Bibcode :2022A&A...657A...7K . doi :10.1051/0004-6361/202142146 . eISSN 1432-0746 . ISSN 0004-6361 .
^ a b c d Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List" . The Astronomical Journal . 158 (4): 138. arXiv :1905.10694 . Bibcode :2019AJ....158..138S . doi :10.3847/1538-3881/ab3467 . eISSN 1538-3881 .
^ a b McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (21 November 2012). "Fundamental parameters and infrared excesses of Hipparcos stars: Parameters and IR excesses from Hipparcos" . Monthly Notices of the Royal Astronomical Society . 427 (1): 343– 357. arXiv :1208.2037 . Bibcode :2012MNRAS.427..343M . doi :10.1111/j.1365-2966.2012.21873.x . ISSN 0035-8711 .
^ a b c Luck, R. Earle (2 May 2014). "Parameters and Abundances in Luminous Stars" . The Astronomical Journal . 147 (6): 137. Bibcode :2014AJ....147..137L . doi :10.1088/0004-6256/147/6/137 . eISSN 1538-3881 . ISSN 0004-6256 .
^ 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 .
^ 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 .
^ "del TrA" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved August 15, 2022 .
^ Eggleton, P. P.; Tokovinin, A. A. (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 , S2CID 14878976 .