‘15 minutes of terror’: What should happen in the final minutes of Chandrayaan-3 lander’s descent on the Moon

The critical technical manoeuvre that the Chandrayaan-3 lander will have to perform on August 23 when it enters the final 15 minutes of its attempt to make a soft landing on the Moon will be to transfer its high-speed horizontal position to a vertical one — in order to facilitate a gentle descent on to the surface.

These final 15 minutes on Wednesday evening will determine the success of the mission. In July 2019, after the Indian Space Research Organisation (ISRO) aborted the first attempt to launch the Chandrayaan-2 mission, K Sivan, then chairman of India’s space research body, had described this phase as “15 minutes of terror”.

Dr Sivan’s description captured the essence of the complexity of the mission’s final phase — the one in which Chandrayaan-2 failed after the Vikram lander did not switch appropriately from the horizontal to the vertical position, and hurtled on to the surface of the Moon when it was entering the “fine braking phase” 7.42 km from the lunar surface.

The key focus now is on the final landing phase scheduled for Wednesday (August 23) evening — with the final 15 minutes (where the landing failed in the Chandrayaan 2 mission) holding the key to a successful mission