Mapping Coordinate System Irregularities On The Celestial Sphere

Abstract

Various techniques have been used to evaluate and describe coordinate system irregularities. The basic techniques have developed from simple differences to differences in coordinate “bins” to full spherical and cylindrical harmonic treatments. We are undertaking a 15-year program of minor planet observation with the express purpose of finding basic parameters of the adopted fundamental system with respect to a dynamical reference frame. The program is expected to provide a few hundred observations per year of 34 minor planets selected for their distribution of physical and orbital characteristics. The ability of the program to contribute to our knowledge of the rotation of the fundamental system and systematic irregularities within the system will depend on the accuracies of the observations and the distribution of the observations over the orbits and over the celestial sphere. We are considering the use of splines as a method of evaluating systematic corrections to the extant fundamental system. The initial development of the formalism and prospects for evaluation are presented.