Isotopic variations of solar planetary materials caused by neutron capture reactions in space

149Sm-150Sm and 157Gd-158Gd isotopic shifts of solar planetary materials caused by neutron capture reactions have been utilized to characterize the cosmic-ray exposure (CRE) conditions of the individual materials in space. This paper reviews the results of Sm and Gd isotopic shifts for four kinds of planetary materials: enstatite chondrites (aubrites), iron and iron meteorites, lunar soils, and lunar meteorites, and their application with a view to understanding the relationship between the CRE histories and the evolution processes for individual planetary materials as addressed in my previous studies.