Last 15 minutes very crucial, Vikram landing on August 27 if something goes wrong with Chandrayaan: ISRO scientist

Ahmedabad: If any factor appears unfavourable, ISRO will land the Vikram module on the Moon's surface on August 27, a top ISRO official said.

The original landing of the Viram module is scheduled around 6:04 pm on August 23.

"On August 23, two hours before Chandrayaan-3 lands on the Moon, we will take a decision on whether or not it will be appropriate to land it at that time based on the health of the lander module and the conditions on the Moon," ISRO's Space Applications Centre Director (Ahmedabad) Nilesh M Desai told a section of media.

"In case, if any factor appears to be unfavourable, then we will land the module on the Moon on August 27. No problem should occur and we will be able to land the module on August 23," he added.

The Ahmedabad-based ISRO scientist said that the decision regarding the landing will be taken based on the health of Vikram Lander, and the conditions on the Moon.

The last 15 minutes of the landing is a very crucial phase of Chandrayaan-3 mission because there are chances of crash landing if the speed of the Vikram module is not controlled.

"It is not that difficult to land the module on the North Pole of the Moon. But at the south pole of it, there are big craters and boulders. So, it will be very difficult to land the module safely and softly. Our focus will be on reducing the velocity of the lander from 1.68 km/sec because the Moon's gravitational force also plays a part," he said.

Asked what would happen if Vikram Lander is nowhere near the landing site, Desai said it would make an automatic landing with the help of an emergency mode, depending on the surface.

Chandrayaan-3's timeline for today

Chandrayaan-3 mission is on schedule and sailing smooth for a soft landing on the South Polar Region of moon today evening.

The systems are undergoing regular checks and the Mission Operations Complex (MOX) was buzz with energy and excitement.

The live telecast of the landing operations at MOX/ISTRAC will begin at 1720 hrs on August 23, 2023.

ISRO sources said The powered descent of lander for a soft landing on the Moon's surface will take place from a height of about 25 km with a speed of 1.6 km per second.

The focus of ISRO scientists will be on reducing that speed since the Moon's gravitational force will also play a part.

The lander will begin its moon landing descent at 6.04 p.m., two hours after the commands were uploaded and the telemetry signals were analysed.

The soft landing is a tricky and challenging task as it involves a series of complex manoeuvres that included rough and fine braking.

Prior to landing, imaging of the landing site will be done for locating safe and hazard-free zones.

The lander will descend towards the moon in a horizontal position and the Scientists in the MOX at ISRO Telemetry, Tracking and Command Network (ISTRAC), Bengaluru will deploy the commands for fine braking.

The lander’s position will be changed to vertical and in that position, it will hover over the moon, take pictures, survey the landing zone and decide on the safe landing spot.

The Chandrayaan-3 is aimed at the lunar south pole, a region with water ice, or frozen water, that could be a source of oxygen, fuel and water for future moon missions or a more permanent moon colony.

Chandrayaan-3 is expected to remain functional for two weeks if Vikram soft-lands successfully.

The approved cost of Chandrayaan-3 is Rs 250 crores (excluding launch vehicle cost). (UNI)