Quadrupole moment of the sun and the planetary orbits

Abstract

The orbital planes of the planets do not coincide with the Sun's rotational equator. This should be taken into account when calculating the effect of the Sun's quadrupole moment of mass on the planetary orbits. With the current planetary data and a recent value of J<SUB>2</SUB>, the differences between the exact results and the results of the equations using the approximation of coincident planes are not significant. However, they may well become significant should the accuracy of the planetary data improve or a larger value of J<SUB>2</SUB> be found.