Seismology of the Moon and Implications on Internal Structure, Origin and Evolution

Abstract

The objective of the passive seismic experiment is to measure vibrations of the lunar surface produced by all natural and artificial sources of seismic energy and to use these data to deduce the internal structure and constitution of the Moon, the nature of tectonic processes which may be active within the Moon, the rate of strain energy release for the lunar body, and the numbers and masses of meteroroids striking the lunar surface. The instrument used is also capable of measuring changes in gravity and tidal tilts which occur in its vicinity. To accomplish these objectives, seismic data must be combined with data from laboratory measurements of the physical and chemical properties of surface rocks, and many other geophysical and geochemical measurements. Thus far, we have had the opportunity to record data from two lunar seismic stations which were installed by the astronauts during Apollo missions 11 and 12. The combined recording time from these stations is presently over 9 months, but there was no overlap to permit recording the same event at two stations. Results from the analysis of these data have been presented by the seismic experiment team in five previous papers.