India is all set to launch Chandrayaan-3, its third mission to the moon, hoping to make its mark as the fourth country to achieve a successful soft landing on the lunar surface. The launch, scheduled for Friday at 2:35 pm, is a testament to India's perseverance and ambition in space exploration, with the nation making a second attempt to accomplish what its predecessor, Chandrayaan-2, could not.

Despite the failed landing attempt of Chandrayaan-2, the Indian Space Research Organisation (ISRO) has not lost momentum. Instead, the organization has turned failure into a learning experience, taking insights from the previous mission to optimize Chandrayaan-3. Now let's take a look at what this new mission entails and the changes that have been made.

A Refined Approach to the Mission

Following the launch, the spacecraft will incrementally elevate its orbit to escape Earth's gravitational pull. Once the spacecraft has manoeuvred itself into the moon's gravitational field, it will work to reduce its orbit to a 100x100 km circle. This entire process, known as a Hohmann Transfer Orbit, will take around 42 days, culminating in a landing slated for lunar dawn on August 23.

The mission will last one lunar day due to the lander and rover's inability to survive the extreme temperature drop during lunar nights. The lander, which houses the rover, will separate from the propulsion module and start its powered descent toward the moon, marking the beginning of the exploration phase.

The Shift in the Landing Site

The designated landing location for Chandrayaan-3 is a slight deviation from the previous mission. Situated near the moon's southern pole, this new site has been selected due to its potential to harbour water ice and precious minerals, a treasure trove for space exploration.

The shift in the landing site has been influenced by images captured by the Chandrayaan-2 orbiter. Although the current mission lacks its orbiter, it will utilize data from Chandrayaan-2 to navigate the lunar terrain effectively and ensure a smooth landing.

Lessons Learned: Adjustments in Design

Learning from the failure of Chandrayaan-2, ISRO has implemented changes to the current mission that is "failure-based." This methodology focuses on anticipating possible issues and developing solutions to address them.For instance, the landing area has been expanded to a 4kmx2.4km area, providing a wider margin for a safe landing.

The lander has been given additional fuel for a potentially longer journey to the landing site or an alternate location if required. The lander's dependency on capturing in-flight images for landing has been reduced, and the vehicle's physical structure has been enhanced, including removing one of the central thrusters and strengthening the legs.

Consistent Scientific Payloads and a New Addition

The scientific payloads on Chandrayaan-3 remain the same as the previous mission, including apparatus to study lunar quakes, thermal properties of the lunar surface, changes in the plasma near the surface, and a NASA-provided instrument for measuring the precise distance between Earth and the moon.

An exciting new experiment, called Spectro-polarimetry of Habitable Planet Earth (SHAPE), has been added to the propulsion module. This experiment will stay in lunar orbit for three to six months, with its objective being to identify potentially habitable smaller planets by analyzing the reflected light.

Conclusion

Chandrayaan-3, India's latest lunar mission, represents the nation's steadfast commitment to exploring the final frontier. By learning from past experiences and refining its approach, ISRO is well-poised to turn the lessons of Chandrayaan-2 into a success story with Chandrayaan-3. Regardless of the mission's outcome, the launch signals a significant leap forward in India's space exploration journey.