Establishing the age of the Moon is critical to understanding solar system evolution and the
formation of rocky planets, including Earth. However, despite its importance, the age of the
Moon has never been accurately determined. We present uranium-lead dating of Apollo 14
zircon fragments that yield highly precise, concordant ages, demonstrating that they are
robust against postcrystallization isotopic disturbances. Hafnium isotopic analyses of the
same fragments show extremely low initial 176Hf/177Hf ratios corrected for cosmic ray …