CroCube, launched on December 21, 2024 aboard SpaceX’s Falcon 9 (Bandwagon-2), is Croatia’s first satellite led by a young team of engineers and students. Owned and operated by a non-profit organization, this 1U CubeSat marks a step toward the country’s independent space capability. The modular platform enabled rapid subsystem integration and flexible payload deployment. A key innovation lies in its modular Attitude and Orbit Control System (AOCS), developed atop a flight-proven onboard computer (OBC) and standalone GNSS receiver. Instead of developing the whole solution, the team engineered a compact motherboard that integrates magnetorquers, sensors, and driving circuits—showing both efficiency and adaptability. The same OBC type also controls the satellite’s primary camera, demonstrating the platform’s modularity. A standout example of this adaptability is the late-stage addition of Astrotron1000, an experimental payload developed by Croatian company PulsarLabs. Developed just few months before final assembly, it replaced a previous payload with no need for structural or electrical changes. Astrotron1000 compares light sensors in orbit and implements a novel voting mechanism between three onboard microcontrollers to validate sensor data, showcasing both technical ambition and platform flexibility.

Mission goals included successful launch and deployment, verification of all subsystems, public engagement, and payload operations. All primary goals have been achieved: the satellite is fully operational, beaconing regularly, downlinking telemetry, and performing in-orbit testing of both the modular subsystems and Astrotron1000, the onboard camera is fully functional and has successfully transmitted images from orbit. The mission also succeeded in engaging the wider public and student community, inspiring new interest in STEM and space in Croatia and beyond.