In a historic achievement, the Indian Space Research Organisation (Isro) successfully docked its SpaDeX satellites in space, making India the fourth country in the world to possess rendezvous, docking, and undocking capabilities.
The docking experiment, which took place in the wee hours of January 16, 2025, was a meticulous dance between two satellites as the chaser aligned with the target satellite in a tango choreographed by engineers from the Indian space agency.
The SpaDeX mission involved two satellites: SDX01 (Chaser) and SDX02 (Target), each weighing approximately 220 kg as they navigated their way in the coldness of space, aligning together for the docking.
“Manoeuvre from 15m to 3m hold point completed. Docking initiated with precision, leading to successful spacecraft capture. Retraction completed smoothly, followed by rigidisation for stability. Docking successfully completed,” Isro said in an update.
Launched on December 30, 2024, aboard the PSLV C60 rocket from the Satish Dhawan Space Centre in Sriharikota, the satellites were initially positioned in a 475-km circular orbit.
Following a series of maneuvers, they successfully closed the gap from an initial distance of 1.5 km to just 3 meters apart before achieving a successful docking.
Isro had initially scheduled the docking for January 7 and then January 9 but faced technical challenges that led to postponements. The Indian space agency then did attempted to dock on January 11 but it was aborted moments before the docking.
However, after careful evaluations and adjustments, the agency confirmed that both satellites were in good health and ready for the docking process. The successful handshake is being celebrated as a pivotal step for India’s aspirations in space exploration.
This epic docking positions India among global leaders in space technology. The successful demonstration of autonomous docking is crucial for future missions, including lunar exploration and the development of the Bharatiya Antariksh Station (BAS).
The SpaDeX mission is not only a highlight of Isro’s engineering capabilities but also signifies India’s growing ambitions in space.
With this landmark achievement, India joins an elite group of nationsnamely the United States, Russia, and Chinathat have mastered in-space docking technology.
This capability is essential for complex missions requiring multiple spacecraft to work in tandem, paving the way for India’s future endeavours in deep space exploration and potential crewed missions to the Moon by 2040.
The docking experiment also opens the path for Chandrayaan-4 mission, which will be conducted in multiple launches with a significant technical challenge being docking above the Moon to return rocks and soil samples from the lunar surface.