Produced by: Tarun Mishra Designed by: Manoj Kumar
Indian Space Research Organisation (ISRO) has achieved a significant milestone by successfully bringing back the Chandrayaan-3 Propulsion Module (PM) to Earth's orbit from the Moon’s orbit.
According to ISRO, the propulsion module, initially intended for lunar operations, surpassed its primary objectives, leading to its return to Earth's orbit after the Chandrayaan-3 mission fulfilled its goals. The module will be now used for Earth's observation.
Vikram Lander, part of the Chandrayaan-3 mission, achieved a historic touchdown on the Moon on August 23, making India, the first country to land on the Lunar South Pole.
With the primary mission objectives accomplished, ISRO focused on the surplus fuel of the PM, employing innovative mission strategies to extend its operational life for future lunar missions.
Careful planning and maneuverings allowed ISRO to adjust the PM's trajectory, transitioning it from lunar orbit to Earth orbit to avoid potential collisions with the Moon or Earth's GEO belt.
The initial maneuver, executed on October 9, 2023, involved raising the apolune altitude from 150 km to 5112 km, resulting in an extended orbit period from 2.1 hours to 7.2 hours. Subsequently, considering the available propellant estimate, the plan for the second maneuver was adjusted to target an Earth orbit ranging from 1.8 lakhs x 3.8 lakhs km.
In the orbit achieved after the Trans-Earth Injection (TEI) maneuver, the propulsion module conducted four fly-bys around the Moon before departing its Sphere of Influence (SOI) on November 10. Presently, the propulsion module is in Earth's orbit and experienced its initial perigee crossing on November 22, reaching an altitude of 1.54 lakhs km. With an orbit period of approximately 13 days and an inclination of 27 degrees, both perigee and apogee altitudes vary along its trajectory, with the predicted minimum perigee altitude at 1.15 lakhs km.
Following the planned schedule, the SHAPE payload is activated whenever Earth comes into its field of view. Additionally, a specific operation of the SHAPE payload was conducted on October 28, 2023, coinciding with a Solar Eclipse.
ISRO has highlighted key achievements resulting from the return maneuvers, encompassing trajectory planning for transitions from the Moon to Earth, the development of software modules for maneuver planning, successful execution of gravity-assisted flybys, and the prevention of uncontrolled crashing to adhere to debris creation standards.
The successful repositioning of the PM not only extends its mission life but also contributes valuable insights and capabilities for future lunar missions, demonstrating ISRO's evolving expertise in space exploration technology.