Chandrayaan-3 was launched on July 14, 2023, from the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh, as the third Moon mission by Indian Space Research Organisation (ISRO) to explore and analyse the Lunar South Pole
Credit: NASA
Before the emergence of Chandrayaan-3, ISRO embarked on two prior attempts at lunar exploration. The maiden voyage, Chandrayaan-1, launched on October 22, 2008, achieved a remarkable feat by discovering evidence of water ice on the Moon's South Pole
ISRO's second lunar mission, Chandrayaan-2, was not without challenges. Launched in 2019, it suffered a partial failure due to a crash-landing, after the lander module started generating excessive thrust and lost balance just 2 km above the Moon's surface. This setback propelled ISRO to embrace change and innovation, leading to the evolution of the Chandrayaan 3 spacecraft
Chandrayaan-2 encountered a high-velocity landing due to accumulated errors on its sensors. Chandrayaan-3's design focuses on mitigating this concern through improved control mechanisms. Chandrayaan-2 grappled with challenges during the landing process, where engine thrust exceeded expectations. Chandrayaan-3 emphasises precise engine thrust dispersion to prevent error accumulation
While the objectives of both Chandrayaan-2 and Chandrayaan-3 align in lunar exploration, their execution diverges significantly. Notably, Chandrayaan-2 boasted an orbiter, lander, and rover, while Chandrayaan 3 replaces the orbiter with a propulsion module and features an instrument for Lunar Seismic Activity (ILSA) on its lander
Chandrayaan-2 weighed 3,850 kg in its entirety, with distinct modules serving specific functions. In contrast, Chandrayaan-3 is a fusion of components, weighing approximately 3,900 kg. This weight includes the propulsion module (2,148 kg), the lander module (1,752 kg), and the rover module (26 kg)
Chandrayaan-2 was crafted for endurance, designed to operate over a 7-year span, promising sustained exploration. In contrast, Chandrayaan-3 adheres to a fixed timeline of 3 to 6 months, necessitating focused and efficient scientific investigations within this limited window
In the realm of hazard detection, Chandrayaan-3 takes a leap forward with two robust cameras, designed to be more resilient than its predecessor's single camera. This enhancement reflects ISRO's determination to overcome challenges faced earlier. Chandrayaan-3 ensures adaptability with a design enabling safe landing anywhere, expanding the landing area to 4km x 2.5km. Abnormal conditions are addressed with additional fuel provisions
Chandrayaan-2's orbiter showcased an array of complex instruments, fuelling comprehensive lunar study. In contrast, Chandrayaan-3's propulsion module debuts the Spectro-polarimetry of Habitable Planetary Earth (SHAPE) instrument. Moreover, Chandrayaan-3's inclusion of the Laser Retroreflector Array (LRA) serves as a secondary experiment, unlocking insights of the dynamic lunar system
The budget of Chandrayaan-2 mission was approximately Rs 978 crores. However, the cost of Chandrayaan-3 mission was estimated at Rs 615 crore, almost Rs 363 crore less than its predecessor
Learning from the problems faced by Chandrayaan-2, ISRO’s Chief S Somanath during an event highlighted that the Chandrayaan-3 is designed so well that it can handle failures. Somnath said, “If everything fails, if all the sensors fail, nothing works, still it will make a landing, That’s how well it has been designed—provided that the propulsion system works well,” reported PTI
The propulsion module separation is scheduled for August 17 and the landing of the lander module ‘Vikram’ is scheduled for August 23. If everything goes according to the plan, ISRO will release the rover module ‘Pragyaan’ on the Lunar South Pole after touchdown for exploration and research