ALPHA PARTICLE EMISSIVITY OF THE MOON--AN OBSERVED UPPER LIMIT,
Abstract
By means of observations with the moon-orbiting spacecraft Explorer 35 during 1967-1968, we find it unlikely that the alpha particle emissivity of the moon is greater than 0.064/square centimeters sec sr to the minus 1 and exceedingly unlikely that it is greater than 0.128, these values being respectively 0.1 and 0.2 of provisional estimates by Kraner et al. in 1966. This result implies that the abundance of 92U238 in the outer crust (nearly equal to a few meters in thickness) of the moon is very much less than that typical of the earth's lithosphere, though it is consistent with the abundance of 92U238 in terrestrial basalt or in chrondritic meteorites. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1969
- Accession Number
- AD0695398
Entities
People
- James A. van Allen
- Richard S. Yeh
Organizations
- University of Iowa