India’s Chandrayaan-3 prioritises fuel efficiency in moon quest

The Indian space programme is setting its course once more for the moon with the third instalment of the Chandrayaan mission. Rock scientists unveiled this revolutionary strategy with a route and experimental approach vastly different from Russia’s Luna-25 probe. The journey, propelled by the gravitational forces of the Earth and Moon, as opposed to heavy reliance on rocket thrusters, will span approximately 40 days, in comparison to Luna-25’s brisk ten-day journey.

The juxtaposition of both missions was laid bare on Saturday when it was revealed that Chandrayaan-3, which was initiated on July 14 from the Satish Dhawan Space Centre in Sriharikota, will make its lunar landing around August 23. This event is scheduled to take place two days after the predicted landing of Luna-25, which was launched successfully on August 11.

The elongated journey time of India’s spacecraft can be attributed to its primary dependence on gravitational forces, a strategy briefly explained by an Indian Space Research Organisation (ISRO) scientist. The reliance on gravitational interplay allows Chandrayaan-3 to be a more fuel efficient and cost-effective mission. As the ISRO official commented, “Our mission might take longer, but we are ensuring that our journey to the moon is extremely fuel-efficient and cost-effective.”

Upon its launch, Chandrayaan-3 was set on an elliptical orbit around Earth, gradually distancing itself from our planet through a series of manoeuvres that increased its orbit incrementally. This carefully calculated strategy will consequently guide the Indian craft into a lunar Orbit. ISRO plans on executing further manoeuvres to reduce the spacecraft’s orbit as it grows closer to its destination.

The ISRO’s modus operandi leans heavily on the concept of frugal innovation, which has been demonstrated in their prior lunar missions, Chandrayaan-1 in 2008, and Chandrayaan-2 in 2019. The agency has prioritised cost-effective strategies over direct, energy-intensive routes. In contrast, Russia’s Luna-25, having at its disposal the powerful Soyuz 2.1 rocket, capitalises on the thruster’s capacity, allowing it a more direct path to the lunar surface instead of an energy-efficient wait in Earth’s orbit.

India’s method of reaching farther shores in space has its limitations, however. The Launch Vehicle Mark-3, previously known as the GSLV MK3, which was used to launch its lunar craft into space, holds significantly less fuel capacity and payload capacity compared to Russia’s Soyuz 2.1.

The goal of Chandrayaan-3, a direct follow-up of the Chandrayaan-2 mission, is to showcase a comprehensive capability of safe landing and roving on the lunar surface. It will send a lander and a rover to the Moon, delivered to a 100km lunar orbit by a propulsion module. Achieving this mission would be a testament to the proficiency and skills harboured within the ISRO agency and undoubtedly an impressive chapter in India’s space exploration story.