ISRO Initiates Automatic Landing Sequence for Chandrayaan-3

Bengaluru: The Indian Space Research Organisation (ISRO) has initiated the Automatic Landing Sequence (ALS) for the Chandrayaan-3 Lander Module (LM). The process began at 05:44 PM. The LM, which comprises the Vikram lander and Pragyan rover, is scheduled to land at 6:04 pm IST, making it a historic achievement for India.

The ALS process began after the LM received the command, activating throttleable engines for a controlled descent. ISRO’s mission operations team will oversee the sequence of commands to ensure accuracy.

Upon confirming parameters, ISRO will upload necessary commands to the LM via the Indian Deep Space Network (IDSN) facility hours prior to the scheduled landing time. As the lander approaches about 30 km above the lunar surface, it enters the powered braking phase. It gradually reduces speed by employing four thruster engines in retrofiring, preventing a crash due to lunar gravity.

Around 6.8 km altitude, two engines remain active, providing reverse thrust for controlled descent. As the LM reaches 150-100 meters above the surface, its sensors and cameras assess obstacles before making a soft landing.

Expected to function for a lunar day (about 14 Earth days), the lander and rover might extend their mission, offering additional insights into the lunar environment.