Navigation Around Small Bodies Using Landed Transponders

Current deep space missions to asteroids and comets rely on extensive imaging and shape-modeling campaigns in order to precisely navigate spacecraft and characterize the dynamic environment. This paper demonstrates how landed transponders can be used to alleviate the operational burdens that conventional landmark-based optical navigation strategies impose. We establish a baseline concept of operations that uses a conventional combination of the Deep Space Network and optical tracking and then perform trades across the number of landed transponders, transponder placement, measurement noise, and small-body parameters. The analysis is split into two mission phases: 1) an initial hyperbolic flyby and 2) a polar circular orbit. We find that landed transponders are able to safely navigate a spacecraft in the vicinity of a small body, achieving key navigation requirements. This, in practice, could facilitate expedited proximity operations, improve radio science return, and may be better suited for autonomous navigation.