Maintaining the desired the thermal balance of a spacecraft in space requires control of solar and thermal radiation. Effectively controlling and unitizing the solar absorption and thermal emission properties of a harvesting device will facilitate thermal balance and enhance the power generation capacity of spacecraft. This will provide advantages for durable spacecraft operation and future short- and long-term space mission success. This project aims to develop an energy harvesting device enabling simultaneous harvesting of incoming solar and outgoing thermal radiation, from both spacecraft and Earth, to generate useful work such as electricity. The proposed device is based upon a non-reflective material made from carbon nanostructured materials for high efficiency absorption of both solar and thermal radiation. This will enable harvesting of direct and Earth-reflected sunlight, as well as collect the outgoing thermal energy radiated from the spacecraft skin and Earth. This material will be combined with a selective thermal emitter to emit energy via thermal radiation at wavelengths that can be collected by thermophotovoltaic cells for conversion to electricity. The ultimate goal is to develop a high-performance device, adaptable to a range of spacecraft, that generates power from the collection of solar and thermal radiation, to meet Air Force needs.