The stability of radiation-induced radicals in solid H^O, C02 and CH4 indicates the possibility of future ESR dating of comets, meteorite impact craters and volcanoes of those solid materials on the outer planets and their satellites. Comet studies with a light-weight ESR instrument will be a first step for ESR investigations in planetary research.-355 -New Applications of Electron Spin Resonance Downloaded from www.worldscientific.com by KAINAN UNIVERSITY on 02/19/15. For personal use only. New Applications of Electron Spin Resonance Downloaded from www.worldscientific.com by KAINAN UNIVERSITY on 02/19/15. For personal use only.