HD 200661
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Equuleus[1] |
| Right ascension | 21h 04m 41.64052s[2] |
| Declination | +02° 56′ 32.1874″[2] |
| Apparent magnitude (V) | 6.41±0.01[3] |
| Characteristics | |
| Evolutionary stage | horizontal branch[4] |
| Spectral type | K0 III[5] |
| U−B color index | +0.89[6] |
| B−V color index | +1.06[6] |
| Astrometry | |
| Radial velocity (Rv) | −12.1±0.2[7] km/s |
| Proper motion (μ) | RA: +13.336[2] mas/yr Dec.: +5.800[2] mas/yr |
| Parallax (π) | 7.5933±0.0353 mas[2] |
| Distance | 430 ± 2 ly (131.7 ± 0.6 pc) |
| Absolute magnitude (MV) | +0.53[1] |
| Details | |
| Mass | 1.22[8] M☉ |
| Radius | 10.64±0.54[9] R☉ |
| Luminosity | 60.59+0.53 −0.52[2] L☉ |
| Surface gravity (log g) | 2.44[8] cgs |
| Temperature | 4,815±122[10] K |
| Metallicity [Fe/H] | −0.21[11] dex |
| Other designations | |
| 7 G. Equueli[12], AG+02°2688, BD+02°4297, GC 29434, HD 200661, HIP 104041, HR 8067, SAO 126519[13] | |
| Database references | |
| SIMBAD | data |
HD 200661 (HR 8067; 7 G. Equueli) is a solitary star located in the equatorial constellation Equuleus, the foal. It has an apparent magnitude of 6.41,[3] placing it near the limit for naked eye visibility. The star is located at a distance of 430 light years based on Gaia DR3 parallax measurements,[2] and it is drifting closer with a heliocentric radial velocity of −12.1 km/s.[7] At its current distance, HD 200661's brightness is diminished by an interstellar extinction of 0.18 magnitude,[14] and it has an absolute magnitude of +0.53.[1]
HD 200661 has a stellar classification of K0 III,[5] indicating that it is an evolved K-type star that has ceased hydrogen fusion at its core and left the main sequence. It has 122% the mass of the Sun,[8] but it has expanded to 10.64 times the radius of the Sun[9] as a result of its evolved state. It radiates 60.59 times the luminosity of the Sun[2] from its enlarged photosphere at an effective temperature of 4815 K,[10] giving it a yellowish-orange hue when viewed in the night sky. HD 200661 is metal deficient with an iron abundance 61.7% that of the Sun's.[11]
References
- ^ a b c Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
- ^ a b c d e f g h 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 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (1 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.
- ^ Gontcharov, G. A. (November 2008). "Red giant clump in the Tycho-2 catalogue". Astronomy Letters. 34 (11): 785–796. arXiv:1607.00619. Bibcode:2008AstL...34..785G. doi:10.1134/S1063773708110078. ISSN 0004-6299. S2CID 73524157.
- ^ a b Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5". Michigan Spectral Survey. 05: 0. Bibcode:1999MSS...C05....0H.
- ^ a b Cousins, A. W. J. (1971). "Photometric standard stars". Royal Observatory Annals. 7. Bibcode:1971ROAn....7.....C.
- ^ a b Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics. 430: 165. arXiv:astro-ph/0409579. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272. S2CID 17804304.
- ^ a b c Anders, F.; et al. (February 2022). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G = 18.5". Astronomy & Astrophysics. 658: A91. arXiv:2111.01860. Bibcode:2022A&A...658A..91A. doi:10.1051/0004-6361/202142369. eISSN 1432-0746. ISSN 0004-6361.
- ^ 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 Bartkevicius, A.; Lazauskaite, R. (January 1, 1997). "Classification of Population II Stars in the Vilnius Photometric System. II. Results". Open Astronomy. 6 (4). Bibcode:1997BaltA...6..499B. doi:10.1515/astro-1997-0402. ISSN 2543-6376. S2CID 201090659.
- ^ 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.
- ^ "HR 8067". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 11 September 2021.
- ^ 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.