HD 101917

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

HD 101917, also designated as HR 4509, or rarely 34 G. Chamaeleontis, is a solitary star located in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude of 6.38, 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 but is receding with a heliocentric radial velocity of 33 km/s. At its current distance, HD 101917's brightness is diminished by 0.28 magnitudes due to interstellar dust. It has an absolute magnitude of +2.69.

HD 101917 has a stellar classification of K0 III/IV, 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, enough time for it to cool and expand to 4.01 times the radius of the Sun. At present it has 126% the mass of the Sun and now radiates 9.04 times the luminosity of the Sun from its enlarged photosphere at an effective temperature 5,076 K, giving it a yellow hue. HD 101917 has an iron abundance 22% below solar levels, making it slightly metal deficient. It spins slowly with a projected rotational velocity lower than 1.4 km/s.

References

  1. 1 2 3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
  2. 1 2 3 4 5 6 7 8 9 10 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.
  3. 1 2 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.
  4. 1 2 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. 1 2 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.
  6. 1 2 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.
  7. 1 2 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. 1 2 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. 1 2 3 4 5 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. 1 2 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. 1 2 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.