HD 169853, also known as HR 6910 or rarely 9 G. Coronae Australis, is a solitary star[15] located in the southern constellation Corona Australis. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.62.[2] Gaia DR3 parallax measurements imply a distance of 391 light years,[1] and it is currently approaching the Solar System with a heliocentric radial velocity of −21.3 km/s.[6] At its current distance, HD 169853's brightness is diminished by 0.36 magnitudes due to extinction from interstellar dust[16] and it has an absolute magnitude of +0.13.[7]

HD 169853
Location of HD 169853 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Corona Australis
Right ascension 18h 28m 27.11405s[1]
Declination −38° 59′ 44.4102″[1]
Apparent magnitude (V) 5.62±0.01[2]
Characteristics
Spectral type A2m A2-F0[3] or A3 III[4]
B−V color index +0.13[5]
Astrometry
Radial velocity (Rv)−21.3±1.2[6] km/s
Proper motion (μ) RA: +0.096 mas/yr[1]
Dec.: −41.093 mas/yr[1]
Parallax (π)8.3424 ± 0.0673 mas[1]
Distance391 ± 3 ly
(119.9 ± 1.0 pc)
Absolute magnitude (MV)+0.13[7]
Details
Mass2.09+0.39
−0.25
[8] M
Radius3.72±0.12[9] R
Luminosity60.7+1.0
−1.1
[1] L
Surface gravity (log g)3.64[10] cgs
Temperature8,437±164[8] K
Metallicity [Fe/H]−0.01[11] dex
Rotational velocity (v sin i)22.6±0.3[12] km/s
Age585+67
−66
[1] Myr
Other designations
9 G. Coronae Australis[13], CD−39°12626, CPD−39°8093, GC 25185, HD 169853, HIP 90541, HR 6910, SAO 210197[14]
Database references
SIMBADdata

HD 169853 has a stellar classification of A2mA2-F0,[3] indicating that it is an Am star with the calcium H lines of an A2 star and the metallic lines of an F0 star. Abt and Morell (1995) give a class of A3 III,[4] indicating that the object is instead an evolved A-type giant star with no chemical peculiarities. A paper published in late 1987 found that HD 169853 had an overabundance of silicon, manganese, strontium, and barium.[17]

The object has 2.09 times the mass of the Sun[8] and a slightly enlarged radius of 3.72 R.[9] It radiates 60.7 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 8,437 K.[8] It has a near solar metallicity at (Fe/H) = −0.01[11] and it is estimated to be 585 million years old, having completed 80% of its main sequence lifetime.[1] Like many chemically peculiar stars, HD 169853 rotates rather slowly, having a projected rotational velocity of 22.6 km/s.[12]

References

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  1. ^ a b c d e f g h i 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. S2CID 17128864.
  3. ^ a b Houk, N. (1982). Michigan Catalogue of Two-dimensional Spectral Types for the HD stars. Declinations −40° to −26°. Vol. 3. Bibcode:1982mcts.book.....H.
  4. ^ a b Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". The Astrophysical Journal Supplement Series. 99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182. ISSN 0067-0049.
  5. ^ Corben, P. M. (April 1971). "Photoelectric Magnitudes and Colours for Bright Southern Stars". Monthly Notes of the Astronomical Society of South Africa. 30 (4): 37. Bibcode:1971MNSSA..30...37C. ISSN 0024-8266.
  6. ^ 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.
  7. ^ 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.
  8. ^ 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. hdl:1721.1/124721. S2CID 166227927.
  9. ^ 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.
  10. ^ 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. S2CID 131780028.
  11. ^ a b Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771–782. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. eISSN 1562-6873. ISSN 1063-7737. S2CID 118345778.
  12. ^ a b Díaz, C. G.; González, J. F.; Levato, H.; Grosso, M. (July 2011). "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum". Astronomy & Astrophysics. 531: A143. arXiv:1012.4858. Bibcode:2011A&A...531A.143D. doi:10.1051/0004-6361/201016386. eISSN 1432-0746. ISSN 0004-6361. S2CID 119286673.
  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. ^ "HD 169853". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 17, 2023.
  15. ^ 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. S2CID 14878976.
  16. ^ 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. S2CID 118879856.
  17. ^ Lodén, L. O.; Sundman, A. (December 1987). "Experiments with CP stars". Journal of Astrophysics and Astronomy. 8 (4): 351–367. Bibcode:1987JApA....8..351L. doi:10.1007/BF02714899. eISSN 0973-7758. ISSN 0250-6335. S2CID 123172433.