56 Leonis
56 Leonis is a red giant variable star located approximately 390 light years away in the constellation Leo.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Leo |
| Right ascension | 10h 56m 01.4690s[1] |
| Declination | +06° 11′ 07.328″[1] |
| Apparent magnitude (V) | 5.69 – 6.03[2] |
| Characteristics | |
| Evolutionary stage | red giant[3] |
| Spectral type | M5.5III[2] |
| Variable type | LB?[2] |
| Astrometry | |
| Proper motion (μ) | RA: −23.90[1] mas/yr Dec.: −6.42[1] mas/yr |
| Parallax (π) | 8.39 ± 0.37 mas[1] |
| Distance | 390 ± 20 ly (119 ± 5 pc) |
| Details | |
| Mass | 1.1[4] M☉ |
| Radius | 192[5] R☉ |
| Luminosity | 1,479[6] L☉ |
| Surface gravity (log g) | 0.64[6] cgs |
| Temperature | 3,279[6] K |
| Metallicity [Fe/H] | +0.45[4] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
The apparent magnitude of 56 Leonis varies between 5.69 and 6.03, making it dimly visible to the naked eye, and it has been given the variable star designation VY Leo. The type of variability is uncertain. The General Catalogue of Variable Stars suggests it may be a slow irregular variable, but some sources have found periods and report it as semiregular.[8]
The spectral class of 56 Leonis is M5.5III, indicating a cool red giant star that has exhausted the supply of hydrogen at its core and evolved away from the main sequence. It is undecided whether it is currently on the red giant branch or asymptotic giant branch.[3] The star has an estimated 1.1[4] times the mass of the Sun but has expanded to 192 times the Sun's radius.[5] The star is radiating 1,479[6] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,279 K.[6]
References Edit
- ^ a b c d e van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- ^ 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 McDonald, I.; De Beck, E.; Zijlstra, A. A.; Lagadec, E. (2018). "Pulsation-triggered dust production by asymptotic giant branch stars". Monthly Notices of the Royal Astronomical Society. 481 (4): 4984. arXiv:1809.07965. Bibcode:2018MNRAS.481.4984M. doi:10.1093/mnras/sty2607. S2CID 118969263.
- ^ a b c Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; De Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy and Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. S2CID 131780028.
- ^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs". Astronomy and Astrophysics. 657: 657. arXiv:2109.10912. Bibcode:2022A&A...657A...7K. doi:10.1051/0004-6361/202142146. S2CID 237605138.
- ^ a b c d e Lebzelter, Thomas; Hinkle, Kenneth H.; Straniero, Oscar; Lambert, David L.; Pilachowski, Catherine A.; Nault, Kristie A. (2019). "Carbon and Oxygen Isotopic Ratios. II. Semiregular Variable M Giants". The Astrophysical Journal. 886 (2): 117. arXiv:1912.04386. Bibcode:2019ApJ...886..117L. doi:10.3847/1538-4357/ab4e9b. S2CID 209140544.
- ^ "Light Curve". Hipparcos ESA. ESA. Retrieved 30 September 2022.
- ^ "VY Leonis". International Variable Star Index. AAVSO. Retrieved 2022-09-29.