The successful launch of the Chandrayaan 2 moon mission gave the Indian Space Research Organisation (ISRO) many anxious moments. Now the satellite is on its way to the moon. And if all goes well, it will soft land on the lunar surface in early September. ISRO Chairman K Sivan spoke to NDTV on how difficult it was to abort the mission on July 15, and how Indian scientists fixed the problem and how "15 minutes of terror" is keeping him awake.