ISRO’s SpaDeX Mission Powers Up with Second Autonomous Docking and Energy Transfer

ISRO’s SpaDeX Mission Powers Up with Second Autonomous Docking and Energy Transfer

In a historic success, ISRO successfully accomplished the second autonomous docking of its SpaDeX satellites—SDX01 (Chaser) and SDX02 (Target)—on April 20, 2025, at 8:20 PM. This operation was fully autonomous from a 15-meter inter-satellite distance, surpassing the first docking in January which involved a manual hold at 3 meters. After the docking, ISRO demonstrated power transfer between the satellites, operating a heater element remotely, marking a critical technology milestone.

This success is touted as a "vote of confidence" in India's fast-growing space ecosystem, which now includes startups and research institutions. It significantly advances docking and undocking technologies that are critical for future missions like Gaganyaan (India's human spaceflight programme), Chandrayaan-4, the lunar sample return mission, and the ambitious Bhartiya Antariksh Station (India's space station). Space experts say that mastering docking is key to modular space structures and will enhance capability to serve and maintain on-orbit.

Union Minister Dr. Jitendra Singh announced the success and stated additional experiments in the forthcoming weeks to further hone these technologies. The SpaDeX mission, executed on December 30, 2024, makes India a part of the select group of countries that have mastered satellite docking, along with the US, Russia, and China.

Source: ISRO official announcements and ancillary news reports