187Re–187Os systematics in meteorites: early chronology of the Solar System and age of the Galaxy

• DOI: 10.1038/283256a0
• Publication Date: 2004-11-17T17:04:51Z
• Authors: Jean-Marc Luck; Jean-Louis Birck; Claude-Jean Allegre
• Keywords: 01 natural sciences; 0105 earth and related environmental sciences

Using isotope dilution mass spectrometry, we have determined the 187Re/186Os, 187Os/186Os ratios of five iron meteorites of various groups, and one ordinary chondrite. These results show that iron meteorites and ordinary chondrites were formed within a short time. We determine the 187Re decay constant as 1.62 ± 0.0310−11 yr−1 and the 187Os/186Os isotopic ratio at the origin of the Solar System as 0.805 ± 0.011. These values are used to compute limits for the age of the Galaxy between 13,300 and 22,400 Myr.