Astronomy:Cayrel's Star
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Cetus |
| Right ascension | 01h 29m 31.1311s[1] |
| Declination | −16° 00′ 45.496″[1] |
| Apparent magnitude (V) | 11.642[2] |
| Astrometry | |
| Proper motion (μ) | RA: 11.745[1] mas/yr Dec.: −42.709[1] mas/yr |
| Parallax (π) | 0.4806 ± 0.0462[1] mas |
| Distance | 6,800 ± 700 ly (2,100 ± 200 pc) |
| Other designations | |
BD−16° 251, CS31082-001, Cayrel's Star | |
| Database references | |
| SIMBAD | data |
BPS CS31082-0001, named Cayrel's Star /keɪˈrɛlz/,[3] is an old Population II star located in a distance of 2.1 kpc[1] in the galactic halo. It belongs to the class of ultra-metal-poor stars (metallicity [Fe/H] = -2.9), specifically the very rare subclass of neutron-capture enhanced stars. It was discovered by Tim C. Beers and collaborators with the Curtis Schmidt telescope at the Cerro Tololo Inter-American Observatory in Chile and analyzed by Roger Cayrel and collaborators. They used the Very Large Telescope (VLT) at the European Southern Observatory in Paranal, Chile for high-resolution optical spectroscopy to determine elemental abundances. The thorium-232 to uranium-238 ratio was used to determine the age. It is estimated to be about 12.5 billion years old, making it one of the oldest known.
Compared to other ultra-metal-poor, r-process enriched stars (as CS22892-052, BD +17° 3248, HE 1523-0901) CS31082-001 has higher abundances of the actinides (Th, U), but a surprisingly low Pb abundance.
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ Munari, U.; Henden, A.; Frigo, A.; Zwitter, T.; Bienaymé, O.; Bland-Hawthorn, J.; Boeche, C.; Freeman, K. C. et al. (2014). "APASS Landolt-Sloan BVgri Photometry of RAVE Stars. I. Data, Effective Temperatures, and Reddenings". The Astronomical Journal 148 (5): 81. doi:10.1088/0004-6256/148/5/81. Bibcode: 2014AJ....148...81M. https://discovery.ucl.ac.uk/id/eprint/10076739/.
- ↑ Space Math @ NASA
Sources
- Beers, T. C., G. W. Preston and S. A. Shectman, A search for stars of very low metal abundance. I., Astron. J., 90, 2089–2102 (1985)
- Beers, T. C., G. W. Preston and S. A. Shectman, A search for stars of very low metal abundance. II., Astron. J., 103, 1987–2034 (1992)
- Cayrel, R., et al. Measurement of stellar age from uranium decay, Nature, Volume 409, Issue 6821, pp. 691–692 (2001)
- Schatz, H., al. Thorium and Uranium Chronometres applied to CS 31082-001, Astrophysical Journal, 579 (2002) 628–638
External links
- "BPS CS 31082-0001". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=BPS+CS+31082-0001.
- arXiv: Measurement of stellar age from uranium decay, R. §Cayrel et al.
- R-Process Cosmo-Chronometers
 |  |
