HD 49268

HD 49268
Observation data
Epoch J2000      Equinox J2000
Constellation Volans
Right ascension 06h 40m 57.6024s[1]
Declination −71° 46′ 30.6872″[1]
Apparent magnitude (V) 6.49±0.01[2]
Characteristics
Spectral type K1 III CNII[3]
U−B color index +1.06[4]
B−V color index +1.11[4]
Astrometry
Radial velocity (Rv)20.6±0.4[5] km/s
Proper motion (μ) RA: +21.453 mas/yr[1]
Dec.: −40.165 mas/yr[1]
Parallax (π)7.1467 ± 0.0222 mas[1]
Distance456 ± 1 ly
(139.9 ± 0.4 pc)
Absolute magnitude (MV)+0.89[6]
Details
Mass1.36[7] M☉
Radius10.77[8] R☉
Luminosity60.2+2.8
−2.7[9] L☉
Surface gravity (log g)2.48[7] cgs
Temperature4,660±90[9] K
Metallicity [Fe/H]+0.07[10] dex
Rotational velocity (v sin i)<1.6[11] km/s
Other designations
2 G. Volantis, CD−71°357, CPD−71°476, HD 49268, HIP 31977, HR 2505, SAO 256326, WDS J06410-7147A[12][13]
Database references
SIMBADdata

HD 49268 (HR 2505) is a solitary star in the southern circumpolar constellation Volans. It has an apparent magnitude of +6.49,[2] placing it near the limit of naked eye visibility. Parallax measurements place the object at a distance of 456 light years;[1] it is receding with a heliocentric radial velocity of 20.6 km/s.[5]

The stellar classification of HD 49268 is K1 III CNII,[3] indicating that it is an ageing red giant with a strong over-abundance of cyano radical in its stellar atmosphere. It has 136% the mass of the Sun[7] but expanded to 10.77 times its girth.[8] It is radiating 60 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,660 K,[9] giving it an orange hue. HD 49268 is slightly metal enriched with an iron abundance 117% that of the Sun and is believed to be a member of the thick disk population.[10] It spins leisurely with a projected rotational velocity that is lower than 1.6 km/s.[11]

HD 49268 has two faint companions listed in the Washington Double Star Catalogue: a tenth magnitude star 17″ away; and a 13th magnitude star 65″ away. Both are unrelated background stars.[14]

References

  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 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 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_ƒ0. Bibcode:1975mcts.book.....H.
  4. ^ a b 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.
  5. ^ 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. ISSN 1063-7737. S2CID 119231169.
  6. ^ 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. ISSN 1063-7737. S2CID 119257644.
  7. ^ a b c Anders, F.; et al. (February 2022). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G = 18.5". Astronomy & Astrophysics. 658: A91. arXiv:2111.01860. Bibcode:2022A&A...658A..91A. doi:10.1051/0004-6361/202142369. eISSN 1432-0746. ISSN 0004-6361.
  8. ^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "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.
  9. ^ a b c Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (January 2020). "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era". Astronomy & Astrophysics. 633: A34. arXiv:1910.12732. Bibcode:2020A&A...633A..34C. doi:10.1051/0004-6361/201936360. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ a b Eggen, O. J. (July 1993). "Evolved GK stars near the sun. I - The old disk population". The Astronomical Journal. 106: 80. Bibcode:1993AJ....106...80E. doi:10.1086/116622.
  11. ^ 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: V. Southern stars⋆⋆⋆". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. ISSN 0004-6361.
  12. ^ "HD 49268". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-01-19.
  13. ^ 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.
  14. ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. ISSN 0004-6256.