Ground-Based Optical Imaging of GEO Satellites with a Rotating Structure in a Sparse Aperture Array

Imaging of geosynchronous (GEO) satellites is a high-interest topic in the field of Space Situational Awareness. Proposed GEO imaging systems often have estimated costs of one hundred million dollars or more, requiring active illumination, one or more very large apertures, and/or space-based assets. Persistent and consistent imaging of the GEO belt would require deploying several such systems around the world, thus it is desirable to seek opportunities to minimize system cost while maintaining sufficient object resolvability. We propose using Michelson Interferometry with a ground-based array of small telescopes to provide the equivalent resolution of a very large filled aperture, thereby significantly reducing the total hardware cost of the system. One or more rotating truss structures can provide azimuthal position rotations to one or more of the apertures in the array, allowing the total number of small telescopes to be reduced in exchange for longer overall collection time and further reducing system cost. We show simulated complex visibility sampling and image reconstructions for several such systems as well as the potential for such systems to be designed to have greater resolution in one direction. Achieving the same resolution without a rotating truss requires nearly ten times as many telescopes.