Why is May 11 observed as the National Technology Day?

May 11 is marked as National Technology Day to commemorate India's technological achievements, including 'Operation Shakti' at Indian Army's Pokhran Range in 1998. It started with three successful nuclear tests, after which India was declared the sixth nuclear state in the world. On the same day, India successfully tested its first indigenous aircraft 'Hansa-3' and short-range missile 'Trishul'.