Chandrayaan-3: With 3 days to touchdown, Lander Module undergoes final deboosting

The Chandrayaan-3 mission's Lander Module (LM) conducted its third and final deboosting on early Sunday thereby moving closer to the Moon.

The ISRO on Sunday said it successfully reduced the orbit of the Chandrayaan-3 mission's LM to 25 km x 134 km, further bringing it nearer to the moon.

The module is expected to touch down on the lunar surface on August 23 evening.

The LM, comprising lander Vikram' and rover Pragyan, will now undergo internal checks and await sunrise at the designated landing site.

The powered descent is expected to commence on August 23, 2023, around 1745 Hrs IST, ISRO said in a post on 'X' (formerly Twitter) on Sunday.

The LM of Chandrayaan-3 successfully separated from the Propulsion Module on Thursday, 35 days after the mission was launched on July 14.

On August 5, Chandrayaan-3 entered the lunar orbit. It carried out orbit reduction manoeuvres on the satellite on August 6, 9, 14 and 16. The crucial separation of the LM from the propulsion module happened on August 17.

It soon underwent the process of deboosting, which means slowing down to place itself in an orbit where the Perilune (the orbit's closest point to the Moon) is 30 kilometres and Apolune (farthest point from the Moon) is 100 km. 

It is from here that the LM will attempt a soft landing on the south-polar region of the Moon.

Just after the first deboosting operation, the ISRO on Friday announced that the health of the LM was normal.

According to the ISRO, the LM will enter the powered braking phase at around 30 km altitude. It will begin to use its thrusters to reach the surface of the moon at an altitude of about 100 m.

The lander would then scan the surface to check whether there are any obstacles and then start descending to make a soft landing.

Chandrayaan-3 is a follow-on mission to Chandrayaan-2 to demonstrate end-to-end capability in safe landing and roving on the lunar surface.

The mission objectives of Chandrayaan-3 are to demonstrate a safe and soft landing on the lunar surface, to demonstrate rover roving on the Moon, and to conduct in-situ scientific experiments.