Chandrayaan-2 lander Vikram, is all set to make its soft landing on the moon on September 7, 2019. The idea behind soft landing revolves around achieving a secure landing with the vehicle unharmed, to increase operational performance. In an interview to Republic, Professor Mayank Vahia, Dean of School of Mathematical Sciences, NMIMS, and formerly at Department of Astronomy & Astrophysics at Tata Institute of Fundamental Research (TIFR), explained that the objective behind soft landing resides in the thought that when the landing is completed, it should land in one piece. He further added that 'even though the machine is comparatively frail, when it lands, the landing should be extremely soft so that in the last 30 to 40 seconds of the landing, the fall can barely be perceived.'
Vikram, the lander is built in a manner where it needs to land on its three legs. If the three legs of Vikram do not land properly on the moon, there will be great difficulty in releasing its rover. Chandrayaan 2's rover is a 6-wheeled robotic vehicle named Pragyan. Pragyan translates to wisdom in English.
Professor Mayank commenting on the nature of the vehicle which will land on September 7, stated, 'even one of those legs of Vikram cannot be tilted. In a scenario where such a thing occurs, there will be a complication. The rationale behind landing soft on the moon resides in the fact that Vikram is landing on a rugged part of the moon, while it is orbiting at great speeds. Therefore, if Vikram is thrown off its balance, there will be no assurance of where or how the machine will make its landing.'
Professor Mayank Vahia spoke of Chandrayaan 1, where the machine had a 29-kilogram piece. He stated it was not a soft landing. The problem with such a landing is since it is a rugged surface, the instruments can break. In the past, there have been instances when the lander is wrapped in a bubble wrap of sorts so when it finally makes its landing, it bounces on and off the ground, eventually settling down. Professor Vahia asserted that while that kind of a process would work on a planet like Mars, the Moon is not ideal for such a process. He noted that the Moon is neither that big nor is its gravitational pull extremely strong, which is why a soft landing is the best possible outcome here, he added.