The Chandrayaan-3 propulsion module is back in orbit around Earth after spending several weeks in lunar orbit, India’s space agency has said, announcing the success of an unplanned experiment to prepare for future “moon-to-Earth” return missions.

The propulsion module that had ferried Chandrayaan-3’s landing modules for the August 23 landing is now in orbit around Earth once every 13 days, brought there through multiple manoeuvres that started on October 9, the Indian Space Research Organisation (Isro) said on Monday.

The return manoeuvres required Isro scientists and engineers to develop a software module for the return trip, plan the trajectory and nudge the propulsion module back into orbit around Earth through multiple firings of its onboard thruster rockets.

The Chandrayaan-3 spacecraft’s precision performance during its exit from Earth orbit and journey towards a lunar orbit in the weeks after its July 14 launch meant that the propulsion module had 100kg fuel onboard after a month in lunar orbit, Isro said.

The decision to use the available fuel for a return trip was taken to gain additional information that could help guide future lunar missions and to evaluate operational strategies for missions designed to bring back lunar samples to Earth, the agency said.

The propulsion module’s return is the second unplanned experiment in Isro's third lunar mission.