New Delhi: The successful docking of two ISRO spacecraft in space on Thursday marks a significant achievement, setting the stage for India’s ambitious future space endeavors. This milestone highlights the nation’s pressing need for a permanent space station to serve as a staging point for long-duration missions.
Docking two fast-moving satellites in space is a highly complex task, requiring precise maneuvering to bring them closer without collision. The two spacecraft, the Chaser and Target, were traveling at speeds of 28,800 km/h—ten times the speed of a bullet. Despite this, they appeared stationary due to zero relative velocity. Over several stages, the Chaser gradually closed the gap with distances of 5 km, 1.5 km, 500 meters, 225 meters, 15 meters, and ultimately 3 meters before successfully docking.
With only the US, Russia, and China having previously mastered this technology, India now joins this exclusive group as the fourth nation to achieve this remarkable feat. ISRO’s scientists have been working on the space docking experiment, known as SpaDeX, since 2016, with accelerated efforts following Prime Minister Narendra Modi’s 2023 directives to establish an indigenous space station by 2035 and a manned lunar mission by 2040. On Thursday, the successful docking of the two 220-kg satellites brought great joy to the ISRO team, especially after overcoming initial challenges.
In a message of congratulations, Prime Minister Modi called the SpaDeX mission “a significant stepping stone for India’s ambitious space missions in the years to come.” He praised the ISRO scientists and the entire space community for their hard work and success, sharing his appreciation on social media. President Droupadi Murmu also extended her congratulations to the team.
Union Space Minister Jitendra Singh emphasized that SpaDeX solidifies India’s position as a global leader in space docking technology. He highlighted the collaboration between ISRO and the Department of Biotechnology to explore the use of biology in space. Singh also stressed the importance of the indigenous ‘Bharatiya Docking System’ and how this achievement paves the way for future missions, including the Bharatiya Antriksha Station, Chandrayaan-4, and Gaganyaan.
Veteran ISRO scientist Nambi Narayanan expressed his excitement, saying the achievement was a long-anticipated dream. “In every future mission, we will need to perfect the docking process for deep space missions. It seems we have mastered it, and it’s a crucial step forward,” he noted. Mylswamy Annadurai, former ISRO scientist and Chandrayaan-1 project director, added that the docking technology will also be vital in managing space debris in future missions.
The primary goal of the SpaDeX mission was to develop and demonstrate the technology for rendezvous docking and undocking of two small spacecraft in low Earth orbit. The mission also tested the transfer of electrical power between docked spacecraft—an essential capability for in-space operations like robotics, spacecraft control, and payload management post-undocking.
The success of SpaDeX has excited India’s space industry. Lt Gen AK Bhatt, Director General of the Indian Space Association (ISpA), called the mission a game-changer, opening up numerous opportunities, particularly as India’s private space sector continues to grow. “This milestone brings us closer to realizing our goals of advancing space programs and eventually establishing a space station,” Bhatt said.
