Rationale and orbital options for a dedicated space-based observatory for NEOs Original Research Article

We present a concept for a dedicated space-based observatory for NEO physical characterization and discovery of objects belonging to orbital classes difficult to observe from the ground (Atens, lEOs). The purpose of such a mission is to derive NEO sizes and albedos using the radiometric technique, and to discover a large fraction of the existing Atens and lEOs during an operational lifetime of a few years. Intrinsic advantages of a space-based platform for reaching the above objectives are discussed, as well as several options for the choice of the satellite orbit. It seems likely that current technology is sufficiently mature to field a relatively inexpensive mission, in which most of the thermal constraints are met by means of passive cooling. The thermal load on the system is greatly reduced if the spacecraft orbits far from the most intense sources of heat, e.g., in the L2 Lagrangian points of the Earth or Venus. Based upon preliminary simulations presented herein the Earth L2 option is the better choice.