India's Chandrayaan-3 satellite went through a battery of tests. The Lander Vikram has been made more robust and the software has been designed in a way that even if everything fails the Lander will be able to make a soft-landing on the lunar surface. NDTV's Pallava Bagla spoke to Professor Radhakant Padhi, an aerospace scientist at the Indian Institute of Science, Bengaluru, who evaluated what went wrong with Chandrayaan-2 and helped ISRO course correct.