Pick-up ion measurements that could be made during the interplanetary cruise of the Cassini spacecraft to Saturn offer a unique opportunity to determine the orientation of the upwind-downwind axis of the heliosphere. The method and results of a feasibility study are presented. The study shows that pick-up oxygen is the best candidate for such a measurement. Model computations are used to predict the actual pick-up oxygen fluxes which instruments on the Cassini spacecraft would see along its trajectory for several currently debated upwind-downwind axis orientations. ¿ American Geophysical Union 1996