EXTRATERRESTRIAL HELIUM TRAPPED IN FULLERENES IN THE SUDBURY IMPACT STRUCTURE

Fullerenes (C-60 and C-70) in the Sudbury impact structure contain tra pped helium with a He-3/He-4 ratio of 5.5 x 10(-4) to 5.9 x 10(-4). Th e He-3/He-4 ratio exceeds the accepted solar wind value by 20 to 30 pe rcent and is higher by an order of magnitude than the maximum reported mantle value, Terrestrial nuclear reactions or cosmic-ray bombardment are not sufficient to generate such a high ratio. The He-3/He-4 ratio s in the Sudbury fullerenes are similar to those found in meteorites a nd in some interplanetary dust particles. The implication is that the helium within the C-60 molecules at Sudbury is of extraterrestrial ori gin.