Chandrayaan-3, the third edition of Indian Space Research Organisation’s lunar mission is in the final stages of its preparation. Chandrayaan-3 is likely to be launched in the second week of July from the Satish Dhawan Space Centre in Sriharikota. Currently, the process of integrating Chandrayaan-3 spacecraft with the GSLV-MkIII rocket is being carried out by ISRO. The rocket will carry Chandrayaan-3 to the Moon.
Chandrayaan-3 comes around four years after the partial failure of the Chandrayaan-2 mission that crash-landed on moon’s surface in 2019. There are some difference between the two moon missions though the mission architecture remains the same.
The difference between the 2nd and 3rd moon missions is in what’s being taken onboard the GSLV-MkIII rocket. While Chandrayaan-2 comprised of Vikram lander, Pragyan rover, and an orbiter, Chandrayaan-3 will launch with just a lander and a rover. It will use the Orbiter already hovering above the Moon launched with Chandrayaan-2 for its communications and terrain mapping requirements.
Through the learnings resulting from the loss of Chandrayaan-2, ISRO had made changes to Chandrayaan-3. The new mission is being launched with Lander Hazard Detection & Avoidance Cameras that will be used to coordinate with the Orbiter and the mission control as the lander makes its descent approach to the surface of the Moon. While Chandryaan-2 had just one such camera, Chandrayaan-3 has been fitted with two such cameras.
The Chandrayaan-2 Orbiter was launched with an impressive list of nine in-situ instruments that are still operating in the Moon’s orbit. This is a big difference between the two missions. In comparison, the propulsion module of the Chandrayaan-3 mission will have just a single instrument named Spectro-polarimetry of HAbitable Planet Earth (SHAPE), which will analyse the spectrum of Earth to generate data for habitable planets. The data will be used to study exoplanets and create a standard to recognise the habitability of the exoplanets found outside the Solar System.
The Laser Retroreflector Array (LRA) being sent with the lander is another addition to the Chandrayaan-3 mission. This is a passive experiment to understand the dynamics of the Moon system. The other three payloads being launched with the mission are the same as that of the Vikram lander on Chandrayaan-2.
ISRO had a failure of the mission with Chandrayaan-2 but the orbiter is there doing measurements and providing data. ISRO worked towards understanding what went wrong and what the problem was. According to ISRO, it was an error in the software that caused the failure of the Chandrayaan-2 mission.
