Precise time synchronization is fundamental to critical infrastructure such as air traffic management, electrical grids, data centers, and financial transactions. Iridium is a satellite constellation that provides precise and secure time synchronization. It employs authentication techniques to prevent spoofing and ensure the delivery of secure, trusted time. However, the protocol used is not openly specified and lacks a thorough security analysis. In this thesis, we aim to conduct a comprehensive security analysis of the Iridium time synchronization protocol. This work has the potential to enhance the trustworthiness of the service, which is essential given its significance in critical applications.