In a groundbreaking move, the Indian Space Research Organisation (ISRO) has successfully shifted the Propulsion Module of Chandrayaan-3 from the Moon’s orbit to an orbit around Earth. Described as a “unique experiment” by ISRO, this maneuver adds another feather to India’s cap in the realm of space exploration.
Unlocking New Frontiers
The Chandrayaan-3 mission, which witnessed the historic touchdown of the Vikram Lander on the Moon’s South Pole on August 23, has now achieved a significant milestone. While the primary goal was to demonstrate a soft landing near the lunar South Pole and conduct experiments using the instruments on Vikram and Pragyaan, the Propulsion Module had a distinct mission.
The main objective of the Propulsion Module was to transport the lander module from the Geostationary Transfer Orbit (GTO) to the final lunar polar circular orbit and execute the separation of the lander. Following this separation, the SHAPE payload in the Propulsion Module was operated, initiating a series of strategic maneuvers.
Strategic Utilization of Fuel Reserves
Optimal orbit injections and carefully planned burn maneuvers resulted in an unexpected surplus of fuel in the Propulsion Module after a month of lunar orbit operations. ISRO seized this opportunity to gather additional information for future lunar missions and demonstrate operational strategies for a sample return mission.
To ensure safety and avoid collisions, the decision was made to reposition the Propulsion Module to a suitable Earth orbit. The mission plan considered factors such as preventing a crash onto the Moon’s surface or entering Earth’s Geosynchronous Equatorial Orbit (GEO) belt. The optimal earth return trajectory was designed, with the first maneuver executed on October 9, 2023.
Successful Earth Orbit Transition
Following meticulous planning and maneuvers, the Trans-Earth Injection (TEI) maneuver on October 13, 2023, propelled the Propulsion Module into Earth’s orbit. The spacecraft executed four Moon fly-bys before departing the sphere of influence (SOI) of the Moon on November 10. Currently, the Propulsion Module is orbiting Earth, with no threat of close approaches to operational Earth-orbiting satellites.
Key Outcomes and Future Prospects
ISRO highlighted several key outcomes of the return maneuvers, including trajectory and maneuver planning for Moon-to-Earth return, software module development for maneuver planning, gravity-assisted fly-by execution, and controlled end-of-life maneuvers to avoid debris creation.
The success of these maneuvers not only accomplishes the objectives of the Chandrayaan-3 mission but also contributes valuable insights and capabilities for future space exploration initiatives.
