Creare and Virginia Polytechnic Institute and State University propose to design, develop, test, and deliver an ultra compact star tracker specifically intended for small satellites such as the CubeSat platform. Our design is based on proprietary "folded optics" technology previously developed by our partner for use in military and commercial optical applications that require a compact footprint and high performance. The folded optics design is superior to conventional refractive optics in miniature star trackers because (1) the compact footprint is achieved without sacrificing accuracy; (2) the light-gathering aperture is much greater, leading to better sensitivity; (3) the aperture geometry makes the shielding baffles smaller; and (4) the imaging sensor can be shielded efficiently from cosmic radiation. During the Phase I project, we will demonstrate the feasibility of our innovation by finalizing the design, performing analysis to determine the optimal design parameters, and testing a benchtop prototype to verify the design models. In Phase II, we will fabricate the optimized design, test the prototype in the laboratory and in the field, and deliver the prototype to NASA.