Measurement of stellar age from uranium decay

  title={Measurement of stellar age from uranium decay},
  author={Roger. Cayrel and Vanessa Hill and Timothy C. Beers and Beatriz Barbuy and Monique Spite and Franccois Spite and Bertrand Plez and J. Andersen and Piercarlo Bonifacio and P. François and Paolo Molaro and B. Nordstr{\"o}m and Francesca Primas},
The ages of the oldest stars in the Galaxy indicate when star formation began, and provide a minimum age for the Universe. Radioactive dating of meteoritic material and stars relies on comparing the present abundance ratios of radioactive and stable nuclear species to the theoretically predicted ratios of their production. The radioisotope 232Th (half-life 14 Gyr) has been used to date Galactic stars, but it decays by only a factor of two over the lifetime of the Universe. 238U (half-life 4.5… Expand
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