HD 92209 (HR 4170) is a probable spectroscopic binary[10] in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude of 6.29,[2] placing it near the max naked eye visibility. Parallax measurements place the system at a distance of 600 light years[1] and is currently receding with a heliocentric radial velocity of almost 18 km/s.[5]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Chamaeleon |
| Right ascension | 10h 35m 24.7604s[1] |
| Declination | −76° 18′ 32.3366″[1] |
| Apparent magnitude (V) | 6.29±0.01[2] |
| Characteristics | |
| Spectral type | K2 III[3] |
| U−B color index | +1.27[4] |
| B−V color index | +1.20[4] |
| Astrometry | |
| Radial velocity (Rv) | 17.8±2.3[5] km/s |
| Proper motion (μ) | RA: −16.952 mas/yr[1] Dec.: +6.489 mas/yr[1] |
| Parallax (π) | 5.4324 ± 0.1144 mas[1] |
| Distance | 600 ± 10 ly (184 ± 4 pc) |
| Absolute magnitude (MV) | −0.03 |
| Details | |
| Mass | 1.22[6] M☉ |
| Radius | 14.39[7] R☉ |
| Luminosity | 81.3+9.9 −8.8[8] L☉ |
| Surface gravity (log g) | 1.76[6] cgs |
| Temperature | 4,460±90[8] K |
| Metallicity [Fe/H] | +0.06[9] dex |
| Rotational velocity (v sin i) | <1[10] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
The visible component has a stellar classification of K2 III,[3] indicating that it is a red giant. As a consequence, it has expanded to 14.39 times the radius of the Sun.[7] Nevertheless, it has 122% the mass of the Sun[6] and shines with a luminosity of 81.3 L☉,[8] yielding an effective temperature of 4,460 K[8] from its enlarged photosphere, which in turn gives an orange hue. HD 92209 has a metallicity 115% that of the Sun[9] and spins leisurely with a projected rotational velocity lower than 1 km/s.[10]
References
edit- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 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. (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.
- ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0. Bibcode:1975mcts.book.....H.
- ^ a b 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 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. ISSN 1063-7737. S2CID 119231169.
- ^ 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. ISSN 0004-6361.
- ^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "Stellar and substellar companions from Gaia EDR3". Astronomy & Astrophysics. 657: A7. arXiv:2109.10912. Bibcode:2022A&A...657A...7K. doi:10.1051/0004-6361/202142146. eISSN 1432-0746. ISSN 0004-6361.
- ^ a b c d Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (January 2020). "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era". Astronomy & Astrophysics. 633: A34. arXiv:1910.12732. Bibcode:2020A&A...633A..34C. doi:10.1051/0004-6361/201936360. eISSN 1432-0746. ISSN 0004-6361.
- ^ a b Eggen, O. J. (February 1994). "Evolved GK stars near the Sun. 2: The young disk population". The Astronomical Journal. 107: 594. Bibcode:1994AJ....107..594E. doi:10.1086/116879. ISSN 0004-6256.
- ^ a b c 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. ISSN 0004-6361.
- ^ "HD 92209". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved June 13, 2022.
- ^ 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.