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Thermal control is a challenge for spacecraft as they must maintain internal components within operating limits despite significant fluctuations in external and internal thermal loads. Satellites often rely on dynamic thermal control to manage internal temperatures depending on the thermal environment. However, many of these systems are actively managed, relying on the satellite’s internal electronics to control the radiator’s behavior. The problem of thermal control is compounded for small satellites, such as CubeSats, which have high power dissipation per unit surface area, stringent size/weight restrictions, and reduced thermal mass. Passive thermal control is particularly attractive for such small systems, potentially offering increased reliability and simplicity. Attempts at passive, dynamic thermal control of spacecraft radiators have been demonstrated in the literature using louvers actuated by bimetallic coils and radiators deployed by shape memory alloys. In this work, we propose a dynamic thermal control method for CubeSats by using bimetallic coils to passively deploy an array of four triangular radiator fins that, when folded, comprise the external face of a CubeSat. This approach differs from previous approaches as it uses mass efficient, triangular radiative fins as well as bimetallic coils to passively actuate the panels, as opposed to shape memory alloys. The advantages of this design include reduced complexity, cost, volume, and weight when compared to traditional deployable radiators in addition to increased redundancy by using an array of panels. An experimental demonstration of the proposed design is presented indicating the ability to passively deploy a single radiator fin using custom bimetallic coils at a rate of approximately 3.9° of angular rotation per 1 °C with minimal hysteresis. A preliminary model of our design indicates the possibility to achieve a turndown ratio of greater than 7:1. Experimental and numerical prediction results are presented as a motivation for exploration of the proposed design in ongoing work.