Chandrayaan 3 lander separates from propulsion module ahead of soft landing: 10 key points

Here are the 10 points that you need to know:

1. 01

   Lander-module separation comes after five manoeuvres

   The Chandrayaan 3 spacecraft was launched on July 14 and entered into lunar orbit on August 5, following which orbit reduction manoeuvres were carried out on August 6, 9 and 14. On August 16, spacecraft successfully underwent a fifth and final lunar-bound orbit manoeuvre. Separation of the lander module from the propulsion module was reported on August 17.

2. 02

   Slingshot manoeuvre sent Chandrayaan 3 towards Moon

   Over five moves in the three weeks since the July 14 launch, ISRO lifted the Chandrayaan 3 spacecraft into orbits farther and farther away from Earth. Then, on August 1 in a key manoeuvre -- a slingshot move -- the spacecraft was sent successfully towards the Moon from Earth's orbit.

3. 03

   Soft landing on lunar pole to be attempted on August 23

   After separation, the lander is expected to undergo a "deboost" (the process of slowing down) to place it in an orbit where the Perilune (closest point to the Moon) is 30 kilometres and Apolune (farthest point from the Moon) is 100 km. From this orbit, the soft landing on the south polar region of the Moon will be attempted on August 23.

4. 04

   Bringing down lander's velocity ahead of final landing biggest challenge

   ISRO chairman S Somanath said the most critical part of the landing is the process of bringing down the velocity of the lander when it begins its descent from a height of 30 km to the final landing (position), and that the ability to transfer the spacecraft from horizontal to vertical direction is the "trick we have to play" here. "It is here where we had the problem last time (Chandrayaan-2)," Somanath explained.

5. 05

   About Chandrayaan 3

   Chandrayaan-3 follows Chandrayaan-2 (2019) to demonstrate end-to-end capability in safe landing and roving on the Moon's surface. It comprises an indigenous propulsion module, lander module, and a rover with an objective of developing and demonstrating new technologies required for inter-planetary missions.

6. 06

   About the SHAPE payload on Chandrayaan's propulsion module

   The propulsion module, other than carrying the lander and rover configuration till about 100 km lunar orbit, carries the Spectro-polarimetry of Habitable Planet Earth (SHAPE) payload to study spectral and polarimetric measurements of the Earth from lunar orbit.

7. 07

   What happens after the lander-module separation?

   Dr M Annadurai, who was Project Director of India's first Lunar Mission Chandrayaan-1, said that after the propulsion module says goodbye to the lander, the lander will have its own initial checkups. "The four main thrusters, which will enable the lander to have a smooth landing on the lunar surface, need to be tested, as well as other sensors. Then it (lander) will take its own course to go to the near 100kmx30km orbit, and from there on August 23 early morning manoeuvres will start," he said.

8. 08

   What are the objectives of the Chandrayaan 3 mission?

   The mission objectives of Chandrayaan-3 are to demonstrate safe and soft landing on the lunar surface, to demonstrate the rover operating on the Moon, and to conduct in-situ scientific experiments. The lander will have the capability to soft land at a specified lunar site and deploy the rover that will carry out in-situ chemical analysis of the Moon's surface during the course of its mobility. The lander and the rover are carrying scientific payloads to carry out experiments on the lunar surface.

9. 09

   The India-Russia lunar race

   India's Chandrayaan-3 and Russia's Luna-25 are gearing up for lunar landings next week, each mission holding significant implications beyond the thrilling competition in the skies. The proximity, possible overlap, of their landing dates -- August 21-23 for Luna-25 and August 23-24 for Chandrayaan-3 -- has attracted global interest. Russia, which is making a momentous return to lunar exploration, its first in almost five decades since the iconic Soviet-era Luna-24 mission in 1976, launched Luna-25 on August 10.

10. 10

    Why lunar missions are important

    The lunar south pole holds particular interest due to its potential water resources and unique geological features. The relatively unexplored region is pivotal for future lunar missions, including the upcoming Artemis-III mission by US space agency NASA, which aims to carry humans to the Moon after a five-decade hiatus.