Cayrel's Star
This article includes a list of general references, but it lacks sufficient corresponding inline citations. (June 2013) |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cetus[1] |
| Right ascension | 01h 29m 31.1311s[2] |
| Declination | −16° 00′ 45.496″[2] |
| Apparent magnitude (V) | 11.642[3] |
| Astrometry | |
| Proper motion (μ) | RA: 11.745[2] mas/yr Dec.: −42.709[2] mas/yr |
| Parallax (π) | 0.4806±0.0462 mas[2] |
| 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/,[4] is an old Population II star located in a distance of 2.1 kpc[2] 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 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 (eg. 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
[edit | edit source]References
[edit | edit source]- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Constellation record for this object at VizieR.
- ^ a b c d e f Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Gaia DR2 record for this source at VizieR.
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Space Math @ NASA
Sources
[edit | edit source]- Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
External links
[edit | edit source]- Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- arXiv: Measurement of stellar age from uranium decay, R. §Cayrel et al.
- R-Process Cosmo-Chronometers
