R Carinae
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,[8] but is usually too faint to be seen without a telescope, having an apparent visual magnitude that fluctuates around 7.43.[5] This star is located at a distance of approximately 1,300 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +28 km/s.[5]
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Carina |
Right ascension | 09h 32m 14.59964s[1] |
Declination | −62° 47′ 20.0452″[1] |
Apparent magnitude (V) | 3.9 - 10.5[2] |
Characteristics | |
Evolutionary stage | AGB[3] |
Spectral type | M6/7pe[4] |
B−V color index | 0.906±0.009[5] |
Variable type | Mira[2] |
Astrometry | |
Radial velocity (Rv) | +28.1±1.0[5] km/s |
Proper motion (μ) | RA: −37.900[1] mas/yr Dec.: +22.232[1] mas/yr |
Parallax (π) | 2.5813 ± 0.4460[1] mas |
Distance | approx. 1,300 ly (approx. 390 pc) |
Absolute magnitude (MV) | 1.48[5] (at mv = 7.43) |
Details | |
Mass | 0.87+0.47 −0.31[3] M☉ |
Radius | 241.0+37.6 −32.6[3] R☉ |
Luminosity | 4,571+1,331 −1,031[3] L☉ |
Temperature | 2,800[6] K |
Other designations | |
Database references | |
SIMBAD | data |
The main component is an aging red giant star on the asymptotic giant branch[3] with a stellar classification of M6/7pe.[4] 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,[8] but the brightest observed maximum was magnitude 3.9[2] 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.[9]
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.[10]
References
- Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S.
- 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.
- Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
- 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.
- 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.
- "R Car". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-30.
- 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.
- 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.
- Mason, B. D.; et al. (2014), The Washington Visual Double Star Catalog, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.