Impact ejection of lunar meteorites and the age of Giordano Bruno

Based on literature data from lunar meteorites and orbital observations it is argued that the lunar crater Giordano Bruno (22 km ∅) formed more than 1 Ma ago and probably ejected the lunar meteorites Yamato 82192/82193/86032 at 8.5 ± 1.5 Ma ago from the Th-poor highlands of the Moon. The efficiency and time scale to deliver 3He-rich lunar material into Earth's sediments is discussed to assess the temporal relationship between the Giordano Bruno cratering event and a 1 Ma enduring 3He-spike which is observed in 8.2 Ma old sediments on Earth.