Space-Based Lock-In Determination of Newton's Gravitational Constant

Abstract

Inspired by a recent ground-breaking space-based measurement of Newton's gravitational constant, we outline a proposal for a general layout of an optimized space-based approach that combines the advantages of a largely disturbance-free environment with lock-in techniques, null coordinates and the method of covariances. The method of covariances, and cross-covariances, is used for an optimized statistical analysis of data originating from two distinct experimental channels. One of two distinct measurement channels relies on an approximately constant acceleration in the gravitational field of static sources masses, while the second channel involves a lock-in measurement based on test and source masses with oscillating coordinates. Conceivable mission parameters are analyzed in terms of the optimum scale for the source masses and launch capabilities of currently available space launch systems. A candidate location for a largely disturbance-free position in geostationary orbit is identified.