SpaDeX satellites back on Earth; Big news for ISRO ahead of touted Chandrayaan-4 mission

THIRUVANANTHAPURAM: In a major success, the Indian Space Research Organisation (ISRO) brought back the two satellites, launched after 21 months. With this, India acquired the technical capability for future human spaceflight missions, such as a space station and Chandrayaan-4, while ISRO summited yet another height in the space sector.

This marks the first time ISRO has controlled satellites throughout their time in space and successfully brought them back to Earth. India has become the fourth nation—following the United States, Russia, and China—to attain this capability.

The satellites launched for the SpaDeX (Space Docking Experiment) — which involves the docking and undocking of satellites — were recovered on the 12th and 13th. These satellites were launched on December 30, 2024. During their mission, they docked and undocked with each other multiple times. The satellites orbited at an altitude of 460 kilometres above the Earth. The experiments were conducted under the control of ISTRAC (ISRO Telemetry, Tracking and Command Network) in Bengaluru.

The first satellite reached Earth at 9:38 PM on the 12th, landing in the southern Indian Ocean, west of Australia. Seven hours later, at 4:35 AM on the 13th, the second satellite also arrived in the Indian Ocean—this time north of Australia, near Aleutian Island.

Confidence sky-high:

• On January 16, 2025, two satellites were successfully docked (joined together) in space.

• They were undocked (separated) on March 13.

• They were docked again on April 20.

• In a significant achievement, during the docking and undocking processes, the navigation systems, power connections, and thermal control systems functioned precisely, ensuring the satellites did not drift from their intended orbit.

• ISRO and India gained confidence after successfully manoeuvring the spacecraft back to Earth.