- The analysis team refused to believe that the accident occurred because of an error in the Automatic Landing Program (ALP)
- According to the scientists who saw an image of Vikram after the crash, the Lander was tilted or uplifted but not much damaged which can be recognized
- There was an official wait for reviving Vikram which stopped with the ending of the lunar day (14 Earth Days) on Friday
CHENNAI: While it is been a two-week-long wait for us with the hope to wake up for Chandrayaan-2 Vikram, the scientists of ISRO knew that it was died in the crash on 7th September, in the early hours. The analysis team refused to believe that the accident occurred because of an error in the Automatic Landing Program (ALP).
The 1,471kg Vikram and 27kg rover Pragyan attached to its belly had a crush on the lunar surface at an astonishing speed of more than 200kmph, and the onboard system probably could not survive that impact, told by the ISRO insiders to TOI. According to the scientists who saw an image of Vikram after the crash, the Lander was tilted or uplifted but not damaged which can be recognized.
“It was like a shadow of Vikram which I saw”, said a scientist after analyzing the image. “Vikram was not on its legs for sure, it was somehow tilted or upturned, and I could see its two protruding legs among the four”.
According to another scientist, Vikram had lost control sometime during the final 10km landing and while it was about 330m (not 2.1km according to the earlier statement by ISRO) above from the lunar surface it also lost contact with the mission control. He added because it was upside down the thrusters which were designed to act like breaks would have functioned as accelerators and hit the lunar surface with the speed of more than 200kmph or maybe faster than that.
As per another ISRO source, in spite of the altitude, Vikram could have survived without being heavily damaged if it had been upright and then the thrusters brought the speed down to 10m/s(36kmph). The shoes should have reacted as a shock absorber if the crash had happened on its legs, he added. The onboard computer and other systems must have been damaged completely, that is why it is no more able to send any signals.
There is a possibility for an error in the landing program written by a team at the UR Rao Satellite Centre, Bengaluru, said by two scientists. A scientist who did not like to be named said that a program is going on to see whether it was properly reviewed before execution or not. For ensuring a soft landing the software program was guiding the various systems for altitude and velocity control during Vikram’s 15-minute descent from moon’s 30km orbit to the surface.
There was an official wait for reviving Vikram which stopped with the ending of the lunar day (14 Earth Days) on Friday. Vikram was designed with the ability to work during these 14 Earth Days, after which the systems would have shut down automatically because of the long, frigid lunar night with a temperature of minus 183 degrees Celsius.
It has always been a challenge to land softly even for the pioneers in lunar exploration like US, Russia, and China, as Landers, often gets puzzled with the shifting centers of gravity, had to be well controlled from great velocity to near zero speed for touching down the lunar surface upright.