Radiation effects in soils from five lunar missions.Optical and high-voltage electron microscopy were used to study radiation-produced defects. There is no systematic decrease in solar flare track distributions in lunar fines even to a depth of 2.5 m. The soil gradually accumulates in thickness; stirring by impacts is usually on a small scale. The accumulation rate at Luna 16 site is far lower than at the Apollo sites; the mean track density in micron-size grains there exceeds one trillion per sq cm; more than 90% of those grains are metamict; the Luna 16 site is at high longitude where electrostatic charging and transport of soil by geomagnetic tail electrons are minimal. A large fraction of soil grains on sloping ground have been isotropically irradiated, suggesting a tumbling downhill motion.-
Document ID
19730035073
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Phakey, P. P.
Hutcheon, I. D.
Rajan, R. S.
Price, P. B. (California, University Berkeley, Calif., United States)