Periodic orbits for sounding Mars’ atmosphere by down- and limb-looking measurements

The Periodic Multi-Sun-Synchronous Orbit allows the planning of observational cycles in which the solar illumination of the observed planet varies regularly, and returns to the initial condition at the beginning of each cycle. In the classical down-looking geometry of observation, this leads to the possibility of reconstructing the temporal evolution of all planetary parameters that are characterised by a typical variation in the solar day. In this paper, such an orbit is proposed to analyse the evolution of Mars’ atmosphere time-varying parameters taking into account, in addition to the down-looking configuration, a limb-looking geometry that works with a solar occultation technique.