CHENNAI, JAN 10 : A day after arresting the excessive drift between the two spacecrafts as part of Spadex docking experiment mission, the Indian Space Research Organisation (ISRO) on Friday evening said the spacecraft were now at a distance of 1.5 km and on hold mode.

Further drift to reduce the distance to 500 m was planned to be achieved by Saturday morning.

The docking experiment was twice deferred due to technical glitch.

In a post on X on SpaDeX Docking update, the Space Agency said “Spacecrafts are at a distance of 1.5 km and on hold mode. Further drift to 500 m is planned to be achieved by tomorrow morning.”

Yesterday, ISRO said “The drift has been arrested and spacecrafts put in a slow drift course to move closer to each other. By tomorrow, it is expected to reach initialisation conditions”. The excessive drift has led to the postponement of docking of the two satellites—Chaser and Target–scheduled for today morning, but was postponed for the second time.

The docking was earlier scheduled on January 7 and was deferred to yesterday as it required further validation through ground simulations and ISRO on Wednesday announced that the docking was deferred again due to excessive drift while making a maneuver.

After ISRO posted “initiated the drift on the Spacecraft-A to move closer from 500 m to 225 m” last evening, a little while later it posted yet another update saying “while making a maneuver to reach 225 km between satellites, the drift was found to be more than expected, post non-visibility period”.

“The planned docking for January 9 (yesterday) at 0800 hrs is postponed. Satellites are safe”. Taking its space journey to the next level and ushering in the New Year 2025 with a bang, ISRO had on December 30 night became the fourth country in the world to launch the Space Docking Experiment technology, key for Human space flight, by successfully launching the PSLV-C60/SPADEX Mission from the SHAR Range Sriharikota.

The Spadex Mission carried two payloads–Spadex-A and Spadex-B, After a flight duration of about 15-16 minutes, the pair of SPADEX satellites, Chaser and Target, each weighing 220 kg, were precisely injected into an eastward 475 km circular orbit with an inclination of 55 degrees.

“The two Spadex satellites were launched by PSLV-C60, independently and simultaneously, into a 475 km circular orbit at 55 deg inclination, with a local time cycle of about 66 days”, ISRO had said.

India became the fourth country in the world to launch the Space Docking experiment Technology after US, Russia and China and the indigenous technology used in this mission is called the “Bharatiya Docking System” and the SpaDEX (Space Docking Experiment) mission that marked a milestone showcasing India’s expertise in spacecraft docking technology.

This mission is vital for India’s future space ambitions, as Docking technology is key for long-term missions like “Chandrayaan-4” and the planned Indian Space Station, besides crucial for the maiden manned “Gaganyaan” mission.

This launch enhanced ISRO’s operational flexibility and expanded its mission horizons.

Apart from the Spadex success, it was also a historic and groundbreaking mission as ISRO scripted history by deploying a record 24 scientific experiments into space aboard the PSLV Orbital Experiment Module-4 (POEM-4) involving the fourth Stage of PSLV, onboard the PSLV-C60 launch vehicle, that revolutionized space tech.

The two scientific instruments in POEM4 has successfully cultivated crops within four days in space and leaves have started emerging from it, besides demonstrating its first walking robotic arm in space.

“With 24 cutting-edge R&D payloads (14 from ISRO, 10 from academia/startups), it pushed boundaries in biological experiments, robotics, SAR imaging, AI labs, and more…A giant leap for science & innovation”, ISRO said.