Gravitational bending of light by planetary multipoles and its measurement with microarcsecond astronomical interferometers

Abstract

General relativistic deflection of light by mass, dipole, and quadrupole moments of gravitational field of a moving massive planet in the Solar system is derived in the approximation of the linearized Einstein equations. All terms of the order of 1 μas and larger are taken into account, parameterized, and classified in accordance with their physical origin. We discuss the observational capabilities of the near-future optical and radio interferometers for detecting the Doppler modulation of the radial deflection, and the dipolar and quadrupolar light-ray bending by Jupiter and Saturn. © 2008 Copyright International Astronomical Union.