HD 46509, also designated as HR 2396, is a solitary star located in the northern circumpolar constellation Camelopardalis, the giraffe. It is faintly visible to the naked eye as a yellowish-orange hued point of light with an apparent magnitude of 5.86.[2] The object is located relatively far at a distance of 791 light-years based on Gaia DR3 parallax measurements,[1] but it is drifting closer with a heliocentric radial velocity of −24.02 km/s.[6] At its current distance, HD 46509's brightness is diminished by interstellar extinction of 0.31 magnitudes and it has an absolute magnitude of −0.98.[7]
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Camelopardalis |
| Right ascension | 06h 40m 32.25255s[1] |
| Declination | +71° 44′ 55.6296″[1] |
| Apparent magnitude (V) | 5.86±0.01[2] |
| Characteristics | |
| Spectral type | G9 III[3] or K0 III[4] |
| B−V color index | +1.19[5] |
| Astrometry | |
| Radial velocity (Rv) | −24.02±0.19[6] km/s |
| Proper motion (μ) | RA: +4.653 mas/yr[1] Dec.: +11.103 mas/yr[1] |
| Parallax (π) | 4.1248 ± 0.0376 mas[1] |
| Distance | 791 ± 7 ly (242 ± 2 pc) |
| Absolute magnitude (MV) | −0.98[7] |
| Details | |
| Mass | 5.64±1.82[8] M☉ |
| Radius | 27.3±0.6[1] R☉ |
| Luminosity | 399±7[1] L☉ |
| Surface gravity (log g) | 2.34±0.11[8] cgs |
| Temperature | 4,675±92[8] K |
| Metallicity [Fe/H] | +0.12±0.05[8] dex |
| Rotational velocity (v sin i) | 1.5±1.2[9] km/s |
| Age | 339+78 −63[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 46509 has a stellar classification of either G9 III or K0 III,[3][4] with both classes indicating that it is an evolved red giant. It is estimated to be 339 million years old,[8] enough time for it to cool and expand to 27.3 times the radius of the Sun.[1] HD 46509 has about 5.6 times the mass of the Sun[8] and it radiates 399 times the luminosity of the Sun[1] from its enlarged photosphere at an effective temperature of 4,675 K.[8] It is metal enriched with an iron abundance 132% that of the Sun's ([Fe/H] = +0.12)[8] and like most giant stars, it spins slowly with a projected rotational velocity of approximately 1.5 km/s.[9]
References
edit- ^ a b c d e f g h i 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. (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.
- ^ a b Wilson, Ralph E.; Joy, Alfred H. (March 1950). "Radial Velocities of 2111 Stars". The Astrophysical Journal. 111: 221. Bibcode:1950ApJ...111..221W. doi:10.1086/145261. eISSN 1538-4357. ISSN 0004-637X. S2CID 122883647.
- ^ a b Halliday, Ian (September 1955). "Luminosity Function and Space Motions of G8-K1 Stars Derived from Spectroscopic Parallaxes". The Astrophysical Journal. 122: 222. Bibcode:1955ApJ...122..222H. doi:10.1086/146080. ISSN 0004-637X. S2CID 119640884.
- ^ Haggkvist, L.; Oja, T. (1970). "Results of BV photometry 1969-70 (Uppsala refractor)". Private Communication. Bibcode:1970Priv.........0H. S2CID 231475662.
- ^ a b Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (January 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 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 f g h i Feuillet, Diane K.; Bovy, Jo; Holtzman, Jon; Girardi, Léo; MacDonald, Nick; Majewski, Steven R.; Nidever, David L. (20 January 2016). "Determining Ages of APOGEE Giants with Known Distances". The Astrophysical Journal. 817 (1): 40. arXiv:1511.04088. Bibcode:2016ApJ...817...40F. doi:10.3847/0004-637X/817/1/40. eISSN 1538-4357. S2CID 118675933.
- ^ a b de Medeiros, J. R.; Mayor, M. (November 1999). "A catalog of rotational and radial velocities for evolved stars". Astronomy and Astrophysics Supplement Series. 139 (3): 433–460. Bibcode:1999A&AS..139..433D. doi:10.1051/aas:1999401. ISSN 0365-0138. S2CID 54046583.
- ^ "HD 46509". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved July 17, 2023.