He was formerly Chairman of
Atomic Energy Commission, in 1976 he became the first chairman of
Maharashtra Academy of Sciences, located in Pune, Maharashtra.
Head of Trombay Nuclear Facility He completed the construction of the
Thorium plant and the plant for the production of nuclear grade
uranium metal at
Trombay, India. His first major challenging assignment was the setting up of the
Plutonium Plant at Trombay in 1959. This was designed and constructed entirely by Indian scientists and engineers under H. N. Sethna as the Project Engineer. The
Uranium Mill at Jaduguda, Jharkhand was also constructed under his guidance in 1967. He was also the Project Manager of a 40 MW reactor called Canada-India Reactor in 1956–58.
Indian atomic test of 1974 He was the guiding force behind the first
peaceful nuclear explosion,
Project Smiling Buddha in India on 18 May 1974, and in 1975, Homi Sethna, then chairman of the
Atomic Energy Commission,
Raja Ramanna and
Basanti Dulal Nagchaudhuri (head of the
DRDO) received the
Padma Vibhushan. ==Awards==