The electrical conductivity of the Moon: an application of inverse theory

Inverse theory of Backus & Gilbert is used to analyse the day-side electromagnetic response of the moon to magnetic fluctuations in the solar wind. The data consist of two transfer functions, both tangential to the lunar surface, and in the theoretical development, the required Fréchet kernels corresponding to these transfer functions are determined. The ensuing calculations show that the data are sufficiently good to determine the conductivity down to a depth of about 600 km. The results are very encouraging and it is suggested that as newer theories of lunar induction are developed to consistently interpret the day-and night-side measurements, they should be used in the above enlightened manner.