HD 193002 (HR 7758; NSV 25094) is a solitary red hued star located in the southern constellation Telescopium. It has an apparent magnitude of 6.26,[2] placing it near the limit for naked eye visibility, even under ideal conditions. The object is located relatively far at a distance of 1,030 light years based on Gaia DR3 parallax measurements,[1] but it is approaching the Solar System with a heliocentric radial velocity of −9.1 km/s.[7] At its current distance, HD 193002's brightness is diminished by 0.17 magnitudes due to interstellar dust[15] and it has an absolute magnitude of −0.93.[8]

HD 193002
Location of HD 193002 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Telescopium
Right ascension 20h 20m 32.31401s[1]
Declination −55° 03′ 03.1837″[1]
Apparent magnitude (V) 6.26±0.01[2]
Characteristics
Evolutionary stage AGB[3]
Spectral type M0/1 III[4]
U−B color index +2.01[5]
B−V color index +1.59[5]
Variable type suspected[6]
Astrometry
Radial velocity (Rv)−9.1±0.4[7] km/s
Proper motion (μ) RA: +9.106 mas/yr[1]
Dec.: −33.290 mas/yr[1]
Parallax (π)3.1785 ± 0.0411 mas[1]
Distance1,030 ± 10 ly
(315 ± 4 pc)
Absolute magnitude (MV)−0.93[8]
Details
Mass1.08[9] M
Radius84.5±4.3[10] R
Luminosity711[11] L
Surface gravity (log g)0.87[9] cgs
Temperature3,972±122[12] K
Metallicity [Fe/H]+0.07[9] dex
Other designations
85 G. Telescopii[13], NSV 25094, CPD−55°9365, FK5 3626, GC 28241, HD 193002, HIP 100300, HR 7758, SAO 246535[14]
Database references
SIMBADdata
A light curve for HD 193002, plotted from Hipparcos data[16]

HD 193002 has a stellar classification of M0/1 III,[4] indicating that it is an evolved red giant with the characteristics of an M0 and M1 giant star. It is currently on the asymptotic giant branch,[3] generating fusion via hydrogen and helium shells around an inert carbon core. It has a comparable mass to the Sun[9] but it has expanded to 84.5 times the radius of the Sun.[10] It radiates 711 times the luminosity of the Sun[11] from its enlarged photosphere at an effective temperature of 3,972 K.[12] HD 193002 is slightly metal enriched with an iron abundance 118% that of the Sun's or [Fe/H] = +0.07.[9]

HD 193002 was first suspected to be variable in 1997 by the Hipparcos satellite.[17] It fluctuates between 6.34 and 6.39 in the Hipparcos passband.[6]

References edit

  1. ^ a b c d e 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 Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun". The Astronomical Journal. 104: 275. Bibcode:1992AJ....104..275E. doi:10.1086/116239. ISSN 0004-6256. S2CID 121672252.
  4. ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars: Declinations −90° to −53°. Vol. 1. Bibcode:1975mcts.book.....H.
  5. ^ a b Oja, T. (1970). "UBV-Fotometri danska Tel (ESO)". Private Communication: 0. Bibcode:1970Priv.........0O.
  6. ^ a b Samus’, N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (January 2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. eISSN 1562-6881. ISSN 1063-7729. S2CID 125853869.
  7. ^ 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.
  8. ^ 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.
  9. ^ a b c d e 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.
  10. ^ 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.
  11. ^ a b McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (21 November 2012). "Fundamental parameters and infrared excesses of Hipparcos stars: Parameters and IR excesses from Hipparcos". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–357. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. eISSN 1365-2966. ISSN 0035-8711. S2CID 118665352.
  12. ^ 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.
  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 193002". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved April 24, 2023.
  15. ^ 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.
  16. ^ EAS (1997). "The HIPPARCOS and TYCHO catalogues". Astrometric and Photometric Star Catalogues Derived from the ESA Hipparcos Space Astrometry Mission. ESA SP Series. 1200. Noordwijk, Netherlands: ESA Publications Division. Bibcode:1997ESASP1200.....E. ISBN 9290923997. Retrieved 15 October 2022.
  17. ^ Perryman, M. A. C.; Lindegren, L.; Kovalevsky, J.; Hoeg, E.; Bastian, U.; Bernacca, P. L.; Crézé, M.; Donati, F.; Grenon, M.; Grewing, M.; van Leeuwen, F. (July 1997). "The HIPPARCOS Catalogue". Astronomy and Astrophysics. 323: L49–L52. Bibcode:1997A&A...323L..49P. ISSN 0004-6361.