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HD 101917

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HD 101917
Location of HD 101917 on the map (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Chamaeleon
Right ascension 11h 42m 54.93206s[1]
Declination −79° 18′ 23.0075″[1]
Apparent magnitude (V) 6.38±0.01[2]
Characteristics
Spectral type K0 III/IV[3]
U−B color index +0.59[4]
B−V color index +0.90[4]
Astrometry
Radial velocity (Rv)32.5±0.4[5] km/s
Proper motion (μ) RA: +127.152 mas/yr[1]
Dec.: −11.599 mas/yr[1]
Parallax (π)17.64 ± 0.0224 mas[1]
Distance184.9 ± 0.2 ly
(56.69 ± 0.07 pc)
Absolute magnitude (MV)+2.69[6]
Details
Mass1.26[7] M
Radius4.01±0.20[8] R
Luminosity9.04±0.03[1] L
Surface gravity (log g)3.32±0.06[9] cgs
Temperature5,076±19[9] K
Metallicity [Fe/H]−0.11±0.02[9] dex
Rotational velocity (v sin i)<1.4[10] km/s
Age3.87+0.41
−0.42
[1] Gyr
Other designations
34 G. Chamaeleontis[11], CD−78°476, CPD−78°677, GC 16083, HD 101917, HIP 57137, HR 4509, SAO 256865[12]
Database references
SIMBADdata

HD 101917, also designated as HR 4509, or rarely 34 G. Chamaeleontis,[11] is a solitary star located in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude of 6.38,[2] placing it near the limit for naked eye visibility. The object is located relatively close at a distance of 185 light years based on Gaia DR3 parallax measurements[1] but is receding with a heliocentric radial velocity of 33 km/s.[5] At its current distance, HD 101917's brightness is diminished by 0.28 magnitudes due to interstellar dust.[13] It has an absolute magnitude of +2.69.[6]

HD 101917 has a stellar classification of K0 III/IV,[3] indicating that it is an evolved K-type star with the blended luminosity class of a subgiant and a giant star. Gaia DR3 models it to be 3.9 billion years old,[1] enough time for it to cool and expand to 4.01 times the radius of the Sun.[8] At present it has 126% the mass of the Sun[7] and now radiates 9.04 times the luminosity of the Sun from its enlarged photosphere at an effective temperature 5,076 K,[9] giving it a yellow hue. HD 101917 has an iron abundance 22% below solar levels,[9] making it slightly metal deficient. It spins slowly with a projected rotational velocity lower than 1.4 km/s.[10]

References[edit]

  1. ^ a b c d e f g h 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 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.
  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. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
  6. ^ a b 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.
  7. ^ a b Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361.
  8. ^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants". Astronomy & Astrophysics. 426 (1): 297–307. arXiv:astro-ph/0404180. Bibcode:2004A&A...426..297K. doi:10.1051/0004-6361:20035930. eISSN 1432-0746. ISSN 0004-6361.
  9. ^ a b c d e Hojjatpanah, S.; et al. (September 2019). "Catalog for the ESPRESSO blind radial velocity exoplanet survey". Astronomy & Astrophysics. 629: A80. arXiv:1908.04627. Bibcode:2019A&A...629A..80H. doi:10.1051/0004-6361/201834729. 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. ^ a b 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.
  12. ^ "HD 101917". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved January 10, 2023.
  13. ^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711.