In outer space, the environment is defined by complete vacuum and radiation in high energy sources such as magnetic radiation, space particles, and cosmic rays. For these extreme environments, the lunar exploration rover, Moonraker, is currently under development, where the core design requires to meet these conditions. In this paper, the thermal architecture of Moonraker is described. Space ready and off-the-shelf but carefully selected hardware is implemented onto the rover, and thermal vacuum testing was conducted to verify the functionality of the rover. Based on the result, the thermal simulation matched close to the experiment; therefore, the model is used as a source of guideline to predict temperature profile at the lunar surface. As a next phase of research, thermal architecture is revised based on the result. The revised architecture is the basis for a real mission to the lunar surface.