HD 201647 (HR 8100; Gliese 9726; LTT 8410) is a solitary star[16] located in the southern constellation Microscopium. It is faintly visible to the naked eye as a yellowish-white-hued star with an apparent magnitude of 5.83.[2] The object is located relatively close at a distance of light-years based on Gaia DR3 parallax measurements, but it is receding with a heliocentric radial velocity of 4.5 km/s.[6] At its current distance, HD 201647's brightness is diminished by 0.11 magnitudes due to interstellar extinction[17] and it has an absolute magnitude of +3.33.[7] It has a relatively high proper motion across the celestial sphere, moving at a rate of 226.331 mas/yr.[18]

HD 201647
Location of HD 201647 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Microscopium
Right ascension 21h 12m 13.71281s[1]
Declination −40° 16′ 09.7010″[1]
Apparent magnitude (V) 5.83[2] (5.83 - 5.86)[3]
Characteristics
Spectral type F5 V[4][5]
B−V color index +0.45[2]
Variable type suspected[3]
Astrometry
Radial velocity (Rv)4.5±0.9[6] km/s
Proper motion (μ) RA: +58.359 mas/yr[1]
Dec.: −218.773 mas/yr[1]
Parallax (π)31.4586 ± 0.0401 mas[1]
Distance103.7 ± 0.1 ly
(31.79 ± 0.04 pc)
Absolute magnitude (MV)+3.33[7]
Details
Mass1.28[8] M
Radius1.47+0.07
−0.04
[9] R
Luminosity3.79±0.01[1] L
Surface gravity (log g)4.21±0.01[10] cgs
Temperature6,637±80[11] K
Metallicity [Fe/H]+0.06±0.01[12] dex
Rotational velocity (v sin i)25.1±2.5[13] km/s
Age916[8] Myr
Other designations
55 G. Microscopii[14], NSV 25506, CD−40°14216, CPD−40°9488, GC 29614, GJ 9726, HD 201647, HIP 104680, HR 8100, SAO 230575, LTT 8410, TIC 159670453[15]
Database references
SIMBADdata

HD 201647 has a stellar classification of F5 V,[5][4] indicating that it is an ordinary F-type main-sequence star that is generating energy via hydrogen fusion at its core. It has 1.28 times the mass of the Sun[8] and 1.47 times the radius of the Sun.[9] It radiates 3.79 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 6,637 K.[11] HD 201647 is slightly metal enriched with an iron abundance of [Fe/H] = +0.06 or 115% of the Sun's.[12] It is estimated to be 916 million years old[8] and it spins modestly with a projected rotational velocity of 25.1 km/s.[13]

In the discovery paper for Lacaille 8760, HD 201647 was reported to be a variable star that varied between 5.83 and 5.86 in the visual passband.[3] As of 2004 however, it has not been confirmed to be variable.[19]

References

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  1. ^ a b c d e f 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 c 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.
  3. ^ a b c Byrne, Patrick B. (June 1981). "Gliese 825 – a new flare star". Monthly Notices of the Royal Astronomical Society. 195 (2). Oxford University Press (OUP): 143–147. Bibcode:1981MNRAS.195..143B. doi:10.1093/mnras/195.2.143. ISSN 0035-8711. S2CID 123025779.
  4. ^ a b Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (2 June 2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. eISSN 1538-3881. ISSN 0004-6256. S2CID 250741593.
  5. ^ a b Adams, Walter S.; Joy, Alfred H.; Humason, Milton L.; Brayton, Ada Margaret (April 1935). "The Spectroscopic Absolute Magnitudes and Parallaxes of 4179 Stars". The Astrophysical Journal. 81: 187. Bibcode:1935ApJ....81..187A. doi:10.1086/143628. eISSN 1538-4357. ISSN 0004-637X. S2CID 121056016.
  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 David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. eISSN 1538-4357. S2CID 33401607.
  9. ^ a b 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.
  10. ^ Allende Prieto, C.; Lambert, D. L. (December 1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: masses, radii and effective temperatures". Astronomy and Astrophysics. 352: 555–562. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. ISSN 0004-6361. S2CID 13365201.
  11. ^ a b Casagrande, L.; Schönrich, R.; Asplund, M.; Cassisi, S.; Ramírez, I.; Meléndez, J.; Bensby, T.; Feltzing, S. (26 May 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s): Improved astrophysical parameters for the Geneva-Copenhagen Survey⋆". Astronomy & Astrophysics. 530: A138. arXiv:1103.4651. Bibcode:2011A&A...530A.138C. doi:10.1051/0004-6361/201016276. eISSN 1432-0746. ISSN 0004-6361. S2CID 56118016.
  12. ^ a b Netopil, Martin (4 May 2017). "Metallicity calibrations for dwarf stars and giants in the Geneva photometric system". Monthly Notices of the Royal Astronomical Society. 469 (3): 3042–3055. arXiv:1705.00883. Bibcode:2017MNRAS.469.3042N. doi:10.1093/mnras/stx1077. eISSN 1365-2966. ISSN 0035-8711. S2CID 119034918.
  13. ^ 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. eISSN 1432-0746. ISSN 0004-6361. S2CID 54046583.
  14. ^ 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.
  15. ^ "HD 201647". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved October 14, 2023.
  16. ^ 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.
  17. ^ 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.
  18. ^ Knapp, Wilfried; Nanson, John (January 2019). "A Catalog of High Proper Motion Stars in the Southern Sky (HPMS3 Catalog)". Journal of Double Star Observations. 15: 21–41. Bibcode:2019JDSO...15...21K.
  19. ^ Samus, N. N.; Durlevich, O. V. (November 2004). "VizieR Online Data Catalog: Combined General Catalogue of Variable Stars (Samus+ 2004)". VizieR Online Data Catalog: II/250. Bibcode:2004yCat.2250....0S.