R Carinae
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Carina |
Right ascension | 09h 32m 14.59610s[2] |
Declination | −62° 47′ 20.0026″[2] |
Apparent magnitude (V) | 3.9 - 10.5[3] |
Characteristics | |
Evolutionary stage | AGB[4] |
Spectral type | M6/7pe[5] |
B−V color index | 0.906±0.009[6] |
Variable type | Mira[3] |
Astrometry | |
Radial velocity (Rv) | +28.1±1.0[6] km/s |
Proper motion (μ) | RA: −36.291 mas/yr[2] Dec.: +19.535 mas/yr[2] |
Parallax (π) | 5.5018 ± 0.3345 mas[2] |
Distance | 590 ± 40 ly (180 ± 10 pc) |
Absolute magnitude (MV) | 1.48[6] (at mv = 7.43) |
Details | |
Mass | 0.87+0.47 −0.31[4] M☉ |
Radius | 400±2 (2013)[7] R☉ 581–652 (2018)[8] R☉ 540±50 (2020)[7] R☉ |
Luminosity | 4,571+1,331 −1,031[4] L☉ |
Temperature | 2,800[9] K |
Other designations | |
Database references | |
SIMBAD | data |
R Carinae is a double star in the southern constellation of Carina. The brighter component is a variable star that can be viewed with the naked eye at peak brightness,[11] but is usually too faint to be seen without a telescope, having an apparent visual magnitude that fluctuates around 7.43.[6] This star is located at a distance of approximately 600 light years from the Sun based on parallax,[2] and is drifting further away with a radial velocity of +28 km/s.[6]
Benjamin Apthorp Gould discovered the variable star, in 1871. It appeared with its variable star designation in Annie Jump Cannon's 1907 work, Second Catalogue of Variable Stars.[12] The main component is an aging red giant star on the asymptotic giant branch[4] with a stellar classification of M6/7pe.[5] It is classified as a pulsating Mira type variable star and its visual brightness varies with an average amplitude of 4.25 magnitudes over a period of 303.99±1.08 d. Its average maximum visual magnitude is 5.05±0.45,[11] but the brightest observed maximum was magnitude 3.9.[3] The pulsations make its size change, in 2014, it was 400 times larger than the Sun, while in 2020 it was 540 times larger.[7] This star is surrounded by a dusty shell, with properties that are consistent with iron-poor silicates or corundum, extending from around three stellar radii outward.[13]
The companion is a magnitude 11.30 star at an angular separation of 2.10″ along a position angle of 132° from the main star, as of 2015.[14]
References
[edit]- ^ "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
- ^ 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.
- ^ a b c Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
- ^ a b c d Takeuti, Mine; et al. (2013), "A Method to Estimate the Masses of Asymptotic Giant Branch Variable Stars", Publications of the Astronomical Society of Japan, 65 (3): 60, Bibcode:2013PASJ...65...60T, doi:10.1093/pasj/65.3.60.
- ^ a b Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
- ^ a b c d e 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, S2CID 119257644.
- ^ a b c Rosales-Guzmán, A.; Sanchez-Bermudez, J.; Paladini, C.; Freytag, B.; Wittkowski, M.; Alberdi, A.; Baron, F.; Berger, J.-P.; Chiavassa, A.; Höfner, S.; Jorissen, A.; Kervella, P.; Bouquin, J.-B. Le; Marigo, P.; Montargès, M. (2024-08-01), "A new dimension in the variability of AGB stars: Convection patterns size changes with pulsation", Astronomy & Astrophysics, 688: A124, arXiv:2405.10164, doi:10.1051/0004-6361/202349112, ISSN 0004-6361
- ^ Rosales-Guzmán, A.; Sanchez-Bermudez, J.; Paladini, C.; Alberdi, A.; Brandner, W.; Cannon, E.; González-Torá, G.; Haubois, X.; Henning, Th; Kervella, P.; Montarges, M.; Perrin, G.; Schödel, R.; Wittkowski, M. (2023-06-01). "Imaging the innermost gaseous layers of the Mira star R Car with GRAVITY-VLTI". Astronomy & Astrophysics. 674: A62. arXiv:2303.00056. doi:10.1051/0004-6361/202245370. ISSN 0004-6361.
- ^ McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012), "Fundamental parameters and infrared excesses of Hipparcos stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- ^ "R Car". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-30.
- ^ a b Vogt, N.; et al. (2016), "Determination of Pulsation Periods and Other Parameters of 2875 Stars Classified As Mira in the All Sky Automated Survey (Asas)", The Astrophysical Journal Supplement Series, 227 (1): 6, arXiv:1609.05246, Bibcode:2016ApJS..227....6V, doi:10.3847/0067-0049/227/1/6, S2CID 119295645.
- ^ Cannon, Annie J. (1907), "Second catalogue of variable stars", Annals of Harvard College Observatory, 55: 1–94, Bibcode:1907AnHar..55....1C, retrieved 8 January 2025
- ^ Ireland, M. J.; et al. (July 2005), "Dust scattering in the Miras R Car and RR Sco resolved by optical interferometric polarimetry", Monthly Notices of the Royal Astronomical Society, 361 (1): 337–344, arXiv:astro-ph/0505112, Bibcode:2005MNRAS.361..337I, doi:10.1111/j.1365-2966.2005.09181.x, S2CID 14724805.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.