Speakers
Description
The CHESS (Constellation of High-Performance Exospheric Science Satellites) mission aims to enhance our understanding of the Earth’s upper atmosphere through direct measurements (species number density, altitude profiles, total electron content, ion population, and dynamics) using two twin 3U CubeSats: Pathfinder 1 & 2. The mission is managed by the student association EPFL Spacecraft Team, which is also responsible for building the entire satellite platform. The scientific payloads are provided by the University of Bern, developing the CubeSatTOF mass spectrometer, and ETH Zurich, developing the GNSS receiver. Pathfinder 1 is scheduled for launch into a circular Sun-synchronous orbit at an altitude of 550 km by the end of 2027, with an operational lifespan of two years, while Pathfinder 2 will follow two years later in an elliptical orbit.
Such satellites in low Earth orbit face challenging thermal conditions due to fluctuating irradiation from alternating light and eclipse phases, combined with varying internal heat dissipation. For the CHESS CubeSat, where most subsystems are designed in-house, tailored thermal management is therefore essential. A robust thermal control system must be designed and simulated to keep all components within safe temperature limits, ensuring reliable satellite operation throughout its mission.
Hence, this study embarks on a comprehensive thermal analysis of the CHESS Pathfinder 1 satellite during orbiting operations using Systema-Thermica. Structured in three parts, it first details the model's geometry, materials, internal heat dissipations, and thermal couplings of the satellites instruments and platform subsystems. Next, it identifies worst-case scenarios and presents the corresponding results for the hot and cold cases. Finally, design modifications and mitigation strategies to ensure all components operate within safe temperature ranges under the various system modes are suggested. These findings not only enhance the CHESS mission's success but also offer valuable insights that can be applied to the thermal design for future CubeSat missions.
