Preliminary Thermal Analysis of a Microsatellite for the Exploration of Asteroid Apophis

Apophis is a well-known Near Earth Asteroid (NEA) that, on April 13, 2029, will experience a close encounter with the Earth. Since it will pass at a distance of approximatively 32000 km from the Earth, this event offers a unique opportunity to study the effects of gravitational interactions on medium-sized asteroids. The European Space Agency (ESA) has announced the RAMSES mission, a satellite equipped with scientific payloads to analyse Apophis’ surface composition and its potential changes during the flyby The present thesis focuses on the preliminary thermal analysis of a microsatellite, based on the concept of the ESA RAMSES mission. The study involved learning to use the Thermal Desktop software, conducting a literature review on thermal control strategies and existing architectures, developing a thermal model, defining mission scenarios, performing a series of thermal analyses, and implementing a thermal control hardware design with validation of the results. The ultimate goal was to select and design the thermal control hardware necessary to ensure mission survivability. The spacecraft must withstand both Low Earth Orbit (LEO) and Deep Space environments, hence requiring a robust thermal design. The entire thermal analysis was conducted using Thermal Desktop, which played a crucial role in modelling the spacecraft’s thermal behaviour and evaluating the performance of different thermal control strategies. The software allowed for the creation of a detailed thermal model, simulation of both steady-state and transient scenarios, and verification of thermal stability under mission conditions. Additionally, custom Python scripts were developed to automate the post-processing of simulation results, enabling efficient data analysis and visualization. This study provided an opportunity to investigate key aspects of spacecraft thermal management, including the thermal modelling of honeycomb sandwich panels, the implementation of heat pipes, and the impact of phase-change materials. The proposed thermal design has been developed, tested, and validated, confirming the effectiveness of the chosen strategy while ensuring appropriate safety margins. This work provides valuable insights into spacecraft thermal management and contributes to the broader understanding of thermal control solutions for deep-space missions.