Prime Minister Narendra Modi addresses during the News9 Global Summit, in New Delhi, Monday, Feb. 26, 2024.
| Photo Credit: PTI

Prime Minister Narendra Modi on Thursday (January 16, 2025) congratulated scientists and engineers at ISRO on the successful docking of two satellites in space.

“Congratulations to our scientists at @isro and the entire space fraternity for the successful demonstration of space docking of satellites. It is a significant stepping stone for India’s ambitious space missions in the years to come,” Mr. Modi said in a post on X.

Space agency Indian Space Research Organisation (ISRO) successfully performed the docking of satellites as part of the Space Docking Experiment (SpaDeX), a crucial step towards several future missions, including setting up of the Bharatiya Antariksh Station.

The two satellites SDX01 (Chaser) and SDX02 (Target) which were launched by the PSLV C60 on December 30, 2024, successfully docked as the space agency officials from the Mission Operations Complex (MOX) at ISRO Telemetry, Tracking, and Command Network (ISTRAC) oversaw the complex docking procedure.

According to ISRO, the SpaDeX mission is a cost-effective technology demonstrator mission for the demonstration of in-space docking using two small spacecraft that was launched by PSLV.

In space, docking technology is essential when multiple rocket launches are required to achieve common mission objectives.

(with inputs from PTI)

Dr. V. Narayanan, Secretary DOS, Chairman Space Commission and Chairman ISRO, congratulated the team ISRO after SpaDeX docking, on January 16, 2025
| Photo Credit: X/@ISRO

The Indian Space Research Organisation (ISRO) in the early hours of Thursday (January 16, 2025) successfully executed the SpaDeX docking experiment making India the fourth country after the USA, Russia and China this historic feat.

The two satellites SDX01 (Chaser) and SDX02 (Target) which were launched by the PSLV C60 on December 30, 2024, successfully docked as the space agency officials from the Mission Operations Complex (MOX) at ISRO Telemetry, Tracking, and Command Network (ISTRAC) oversaw the complex docking procedure.

“Docking Success Spacecraft docking successfully completed! A historic moment. Let’s walk through the SpaDeX docking process: 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. India became the 4th country to achieve successful Space Docking. Congratulations to the entire team! Congratulations to India!,” ISRO posted on X.  

ISRO further added that post docking, control of two satellites as a single object is successful. “Undocking and power transfer checks to follow in coming days,” ISRO said.

Earlier this week, ISRO had moved the satellites within three metres in a trial attempt. It then moved the spacecraft back to safe distance.

The SpaDeX mission is an important project by ISRO which is designed to develop and demonstrate the technology needed for spacecraft rendezvous, docking and undocking using two small satellites.

The demonstration of this technology is essential for futuristic missions such as sending an Indian astronaut on the Moon, sample return from the Moon, the building and operation of the Indian Space Station.

The other objectives of the mission include demonstration of the transfer of electric power between the docked spacecraft which is essential for future applications such as in-space robotics, composite spacecraft control and payload operations after undocking.

According to ISRO, after the docking and undocking events, the spacecraft will be separated and used for application missions.

“After successful docking and rigidization, electrical power transfer between the two satellites will be demonstrated before undocking and separation of the two satellites to start the operation of their respective payloads for the expected mission life of up to two years,” ISRO said.

The SpaDeX Docking was scheduled on January 7 but was postponed.

“The docking process requires further validation through ground simulations based on an abort scenario identified today (Jaunary 6),” ISRO had cited as the reason for the postponement of the experiment.

On January 8, 2025, hours before it was scheduled to carry out the SpaDeX docking experiment, ISRO said that the docking experiment which was scheduled to take place on January 9 has been postponed as the drift between the satellites was found more than expected.

It later arrested the drift between the spacecraft.

ISRO launched the SpaDeX mission on December 30, 2024 from the Satish Dhawan Space Centre in Sriharikota. Few minutes after liftoff, the two satellites (Target and Chaser) weighing about 220 kg each were launched into a 475-km circular orbit as intended.