This work outlines the Phase 0 design of the Lunar Unidentified Celestial Identification & Detection (LUCID) mission, a sub 200 kg micro-spacecraft developed to observe and track objects larger than 3 metres in diameter at the average distance of the lunar orbit. The mission, planned for launch on a Vega-C rocket into a Sun-synchronous orbit at 500 km, aims to enhance space situational awareness in the cislunar region. The spacecraft's optical payload will survey a defined area at least once daily, contributing to the tracking of space debris as space exploration and cislunar activities expand. The LUCID mission concept was developed by 40 students over one week during the 2023 European Space Agency (ESA) Academy Concurrent Engineering Workshop (CEW), using the COMET tool to achieve a concurrent design of both the space and ground segments. This paper details the preliminary design outcomes and subsystem analyses of the LUCID mission.