ArticlesAbundance of Major Elements

Pattern of Bombardment-Produced Radionuclides in Rock 10017 and in Lunar Soil

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Science  30 Jan 1970:
Vol. 167, Issue 3918, pp. 574-576
DOI: 10.1126/science.167.3918.574

Abstract

A large number of radionuclides have been measured as a function of depth in lunar rock 10017 and in bulk fines. Data are reported on 10Be, 22Na, 26Al, 36Cl, 49V, 53mn, 54Mn 55Fe, 56Co, 57Co, and 59Ni and on upper limits for 46Sc, 48V, 51Cr, and 60Co. The results for several nuclides show striking evidence of excess surface production attributable to solar flare particles. Data for short-lived species, 56Co, 57CO, 54Mn, 55Fe, and 22Na, appear consistent with fluxes from known recent events. Long-lived species demonstrate the existence of solar flare protons and alphas at least for the last 105 to 106 years, at fluxes comparable to those now observerved.