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nucleocosmochronology

n. (context astronomy English) A technique for estimating the age of astronomical objects by measuring the relative abundances of isotopes

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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 ( billion years) and of the Galactic thin disk , 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.