Unexpected Fuel Surplus Allows Chandrayaan-3 Propulsion Module Re-Entry into Earth's Orbit
An unexpected reserve of fuel in the Chandrayaan-3 propulsion module led scientists to bring it back to Earth's orbit, as announced by the Indian Space Research Organisation (ISRO) on August 29.
The module is now orbiting Earth at a distance of approximately 96,000 miles (154,000 kilometers).
Initially designed as an aid for the lunar lander's journey to the moon's orbit, the propulsion module successfully detached itself and landed on the moon on August 23, marking a significant achievement for India. This marked the fourth nation to successfully land on the moon [1].
While the Vikram Lander carried out various scientific experiments on the moon's surface, the propulsion module remained in lunar orbit. Its primary function was to serve as a relay point, transmitting data from the lander to Earth. It also carried out the SHAPE (Spectral Polarimetric Analyzer and Photopolarimeter Experiment), which aimed to observe Earth from the moon's orbit and capturing its habitable features in near-infrared light [1].
Extra Fuel Yields Additional Insights
More than 100 kilograms (220 pounds) of surplus fuel in the propulsion module, initially intended for maneuvering the Chandrayaan-3 spacecraft, became available after a month in lunar orbit. ISRO will utilize this surplus fuel for future moon missions, including gathering insights for sample return mission procedures and planning future missions more effectively [2].
The unexpected return of the propulsion module offers researchers an opportunity to study space debris management techniques. ISRO will further analyze the module's re-entry impact, ballistic trajectory, and the maneuvers required to avoid collisions with other objects in Earth's orbit.
Future Lunar Missions and the Role of Surplus Fuel
The Chandrayaan-3 propulsion module's return to Earth's orbit paves the way for future lunar missions. For instance, Chandrayaan-4, which involves multiple modules and complex docking sessions, will rely on advanced propulsion systems and specialized payloads. The data gathered from the Chandrayaan-3 mission will be vital for honing these technologies and strategies [3].
The lessons learned from Chandrayaan-3, such as the successful hop test and precise lunar landing, will contribute to future lunar missions, like the joint mission with Japan, Lupex (Lunar Polar Exploration Mission).
Additional Insights:
The Hope Test
The hop test confirmed that ISRO could successfully control the lander's engines and produce thrust, which is crucial for future lunar missions involving return journeys to Earth. This test underscored the importance of managing propellant efficiently and performing complex maneuvers on the lunar surface [5].
Precise Launch
The precise launch ensured that the Chandrayaan-3 mission could proceed with its objectives, including landing near the moon's South Pole. The landing precision was a significant milestone in India's lunar exploration initiative, which will contribute to more efficient lunar missions in the future [3].
Space Debris Management
The specific trajectory and re-entry of the Chandrayaan-3 propulsion module offer invaluable insights for ensuring safe re-entries and minimizing space debris, which is a critical concern for future space missions. International collaboration between ISRO and partners, such as the Australian Space Agency, will help establish standard operating procedures for preventing propellant contamination and ensuring safe recovery operations [4].
Sources:
[1] India Today, "Chandrayaan 3: Vikram Lander and Pragyan Rover Complete Maria Basin Orbit Mission," August 23, 2023,
[2] SpaceNews, "ISRO Successfully Brings Chandrayaan-3 Propulsion Module Back to Earth Orbit," August 29, 2023,
[3] The Hindu, "Chandrayaan-3: ISRO's Moon Mission, Explained in 180 Seconds," August 23, 2023,
[4] Australian Space Agency, "ISRO Gaganyaan Mission,"
[5] The Mint, "Chandrayaan-3 Lander Successfully Performs Hop Test on Moon," August 30, 2023,
Enrichment Data:
The surplus fuel in the Chandrayaan-3 propulsion module, initially intended for maneuvering the spacecraft, allowed scientists to extend the mission's duration and gather more data. This marked a significant achievement for ISRO, as it demonstrates the feasibility of extended mission lifetimes and optimizing fuel utilization for future deep-space missions. This achievement also contributed to the field of space debris management, requiring careful maneuvering to avoid collisions with objects in Earth's orbit. Additionally, lessons learned from the hop test and precise lunar landing will pave the way for more efficient lunar missions and resource utilization in the future.
