Nucleocosmochronology

Nucleocosmochronology, also known as cosmochronology, is a relatively new technique used to determine timescales for astrophysical objects and events. This technique employs the abundances of heavy radioactive nuclides to calculate the age of formation of astronomical objects in a similar fashion to the dating of rocks in the field of geochronology.

Nucleocosmochronology has already been successfully employed to determine the age of the Sun (4.57±0.02 billion years) and of the Galactic thin disk ((8.8±1.8)×10⁹ y), among others. It has also been used to estimate the age of the Milky Way itself, as exemplified by recent study of Cayrel's Star in the Galactic halo. Limiting factors in its precision are the quality of observations of faint stars, and perhaps more importantly, the uncertainty of the primordial abundances of r-process elements.

See also

• Astrochemistry
• Cayrel's Star (CS31082-001)
• Metallicity
• Nucleosynthesis
• Radiometric dating
• Stellar evolution

References and further reading

• Bahcall et al. (1995, Reviews of Modern Physics 67, 781)
• del Peloso et al., "The age of the Galactic thin disk from Th/Eu nucleocosmochronology I. Determination of Th/Eu abundance ratios." Astronomy & Astrophysics, 434, (2005) 275.
• del Peloso et al., "The age of the Galactic thin disk from Th/Eu nucleocosmochronology II. Chronological analysis." Astronomy & Astrophysics, 434, (2005) 301.
• del Peloso et al., "The age of the Galactic thin disk from Th/Eu nucleocosmochronology III. Extended sample." Astronomy & Astrophysics, 440, (2005) 1153.
• ESO Press Release 02/01: "First Reading of a Basic Cosmic Chronometer with UVES and the VLT." (Accessed 3/8/06)
• Hill et al., "First Stars. I. The extreme r-element rich, iron-poor halo giant CS 31082-001" Astronomy & Astrophysics, 387, (2002) 560-579. (Accessed 3/8/06)