Jump to content

HD 170873

Edit links
From Wikipedia, the free encyclopedia
HD 170873
Location of HD 170873 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Telescopium
Right ascension 18h 34m 31.11856s[1]
Declination −52° 53′ 29.4756″[1]
Apparent magnitude (V) 6.20±0.01[2]
Characteristics
Spectral type K2 III[3]
B−V color index +1.27[4]
Astrometry
Radial velocity (Rv)23.8±0.4[5] km/s
Proper motion (μ) RA: −16.944 mas/yr[1]
Dec.: −42.325 mas/yr[1]
Parallax (π)5.9179 ± 0.0283 mas[1]
Distance551 ± 3 ly
(169.0 ± 0.8 pc)
Absolute magnitude (MV)−0.31[6]
Details
Mass3.20±0.04[1] M☉
Radius22.6±1.2[7] R☉
Luminosity170±2[1] L☉
Surface gravity (log g)1.86[8] cgs
Temperature4,473±122[9] K
Metallicity [Fe/H]−0.01[8] dex
Rotational velocity (v sin i)<1[10] km/s
Age318+30
−31[1] Myr
Other designations
19 G. Telescopii[11], CD−52°8714, CPD−52°11158, GC 25324, HD 170873, HIP 91062, HR 6954, SAO 245559[12]
Database references
SIMBADdata

HD 170873, also known as HR 6954 or rarely 19 G. Telescopii, is a solitary orange-hued star located in the southern constellation Telescopium. It has an apparent magnitude of 6.20,[2] placing it near the limit for naked eye visibility. Gaia DR3 parallax measurements imply a distance of 551 light years[1] and it is currently receding with a heliocentric radial velocity of 23.8 km/s.[5] At its current distance, HD 170873's brightness is diminished by 0.39 magnitudes due to interstellar dust,[13] and it has an absolute magnitude of −0.31.[6]

HD 170873 is an evolved red giant with a stellar classification of K2 III.[3] It has 3.2 times the mass of the Sun but at the age of 318 million years,[1] it has expanded to 22.6 times the Sun's radius.[7] It radiates 170 times the luminosity of the Sun[1] from its enlarged photosphere at an effective temperature of 4,473 K.[9] It has a near-solar metallicity at [Fe/H] = −0.01[8] and spins too slowly for its projected rotational velocity to be measured accurately.[10]

References[edit]

  1. ^ a b c d e f g h i j 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, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars: Declinations −53° to −40°. Vol. 2. Bibcode:1978mcts.book.....H.
  4. ^ 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.
  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 Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants. Surface brightness relations calibrated by interferometry". 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. S2CID 6077801.
  8. ^ a b c 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.
  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. ^ 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.
  11. ^ 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 170873". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved March 2, 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. S2CID 118879856.
Retrieved from "https://en.wikipedia.org/w/index.php?title=HD_170873&oldid=1154746589"