SPADEX (Space Docking Experiment) is an Indian Space Research Organisation (ISRO) technology mission to demonstrate autonomous docking between 2 spacecraft in orbit. The mission will involve two spacecraft (Chaser and Target) rendezvous and docking together, plus testing attitude control of the combined spacecraft under docked conditions. The Chaser and Target spacecraft will then be separated for operating other payload. The mission is critical to develop rendezvous and docking abilities for ISRO’s future human spaceflight and lunar sample return missions.