An analysis of the lunar tides

Abstract

The purpose of this analysis was to determine what information may be deduced about the moon's interior from a measurement of the lunar gravitational tide. Three aspects of the problem were considered: the calculation of the tides on a rigid moon, the amplification factors expected for 14 models of the moon's internal constitution, and the accuracy to which these tides can be measured with an instrument whose performance is similar to that of a LaCoste and Romberg earth-tide gravity meter. It is concluded that it should be possible to measure the lunar monthly tide to about 1 per cent in a 416-day observation with present instrumente and methods of analysis. This accuracy will allow models with fluid cores of radius about ¾ that of the lunar radius to be distinguished from the largely solid models but will not differentiate between the various largely solid models which have been considered.