  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Microscopium |
| Right ascension | 21h 02m 27.16546s[1] |
| Declination | −38° 31′ 51.4904″[1] |
| Apparent magnitude (V) | 5.94[2] |
| Characteristics | |
| Evolutionary stage | red giant branch[3] |
| Spectral type | K2 III[4] or K0 IV[5] |
| B−V color index | +1.15[2] |
| Astrometry | |
| Radial velocity (Rv) | 39±10[6] km/s |
| Proper motion (μ) | RA: +156.842 mas/yr[1] Dec.: −171.108 mas/yr[1] |
| Parallax (π) | 14.358 ± 0.0466 mas[1] |
| Distance | 227.2 ± 0.7 ly (69.6 ± 0.2 pc) |
| Absolute magnitude (MV) | +1.79[7] |
| Details | |
| Mass | 1.03[8] M☉ |
| Radius | 9.15±0.46[9] R☉ |
| Luminosity | 28.8±0.3[1] L☉ |
| Surface gravity (log g) | 2.75[8] cgs |
| Temperature | 4,569±50[10] K |
| Metallicity [Fe/H] | −0.13[8] dex |
| Rotational velocity (v sin i) | 2.7±1.1[11] km/s |
| Age | 8.79+2.32 −2.04[12] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 200073 (HR 8046; 43 G. Microscopii) is a solitary star located in the southern constellation Microscopium 8.5′ northwest of Zeta Microscopii. It is faintly visible to the naked eye as an orange-hued point of light with an apparent magnitude of 5.94.[2] The object is located relatively close at a distance of 227 light-years based on Gaia DR3 parallax measurements, but it is receding with a heliocentric radial velocity of 39 km/s.[6] At its current distance, HD 200073's brightness is diminished by an interstellar extinction of 0.13 magnitudes[15] and it has an absolute magnitude of +1.79.[7] It has a relatively high proper motion across the celestial sphere, moving at a rate of 213 mas/yr.[1]
HD 200073 has a stellar classification of K2 III,[4] indicating that it is an evolved K-type giant that has exhausted hydrogen at its core and left the main sequence. Astronomer David Stanley Evans gave a class of K0 IV,[5] indicating that it is a slightly evolved subgiant that is ceasing hydrogen fusion at its core. HD 200073 is currently on the red giant branch,[3] fusing hydrogen in a shell around an inert helium core. It has a comparable mass to the Sun[8] but at the age of 8.79 billion years,[12] it has expanded to 9.15 times the radius of the Sun.[9] It radiates 28.8 times the luminosity of the Sun[1] from its enlarged photosphere at an effective temperature of 4,569 K.[10] HD 200073 is slightly metal-deficient with an iron abundance of [Fe/H] = −0.13 or 74.1% of the Sun's.[8] It spins modestly with a projected rotational velocity of 2.7 km/s.[11]
References
- ^ a b c d e f g 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.
- ^ 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.
- ^ a b Jones, M. I.; Jenkins, J. S.; Rojo, P.; Melo, C. H. F. (December 2011). "Study of the impact of the post-MS evolution of the host star on the orbits of close-in planets: I. Sample definition and physical properties⋆⋆⋆". Astronomy & Astrophysics. 536: A71. arXiv:1110.6459. Bibcode:2011A&A...536A..71J. doi:10.1051/0004-6361/201117887. ISSN 0004-6361.
- ^ 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.
- ^ a b Evans, D. S.; Laing, J. D.; Menzies, A.; Stoy, R. H. (1964). "Fundamental data for southern stars (fifth list)". Royal Greenwich Observatory Bulletins. 85: 207–224. Bibcode:1964RGOB...85..207E.
- ^ a b Kharchenko, N.V.; Scholz, R.-D.; Piskunov, A.E.; Röser, S.; Schilbach, E. (November 2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten. 328 (9): 889–896. arXiv:0705.0878. Bibcode:2007AN....328..889K. doi:10.1002/asna.200710776. eISSN 1521-3994. ISSN 0004-6337. S2CID 119323941.
- ^ 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.
- ^ a b c d e Wittenmyer, Robert A.; Liu, Fan; Wang, Liang; Casagrande, Luca; Johnson, John Asher; Tinney, C. G. (June 24, 2016). "The Pan-Pacific Planet Search. V. Fundamental Parameters for 164 Evolved Stars". The Astronomical Journal. 152 (1). American Astronomical Society: 19. arXiv:1605.00323. Bibcode:2016AJ....152...19W. doi:10.3847/0004-6256/152/1/19. ISSN 1538-3881. S2CID 55991800.
- ^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (April 8, 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.
- ^ 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.
- ^ 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.
- ^ a b Soto, M. G.; Jones, M. I.; Jenkins, J. S. (March 2021). "SPECIES. II. Stellar parameters of the EXPRESS giant star sample". Astronomy & Astrophysics. 647: A157 (23). arXiv:2009.03371. Bibcode:2021A&A...647A.157S. doi:10.1051/0004-6361/202039357. eISSN 1432-0746. ISSN 0004-6361. S2CID 221534230.
- ^ 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.
- ^ "HD 200073". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved November 11, 2023.
- ^ 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.
This page was last edited on 12 November 2023, at 20:08