Rajagopala Chidambaram: The Physicist Behind Two Nuclear Tests

Rajagopala Chidambaram was an Indian physicist. He worked on India’s nuclear programme for decades.

What are the basic facts?

• He was born in 1936.
• He studied at Presidency College, Chennai.
• He then studied at the Indian Institute of Science (IISc), Bengaluru.
• He earned his PhD from IISc in 1962.
• He joined the Bhabha Atomic Research Centre (BARC) the same year.
• He died on 4 January 2025 at Jaslok Hospital, Mumbai, aged 88.

What is the memory hook?

Think “PhD 1962, BARC 1962”. The two steps came in one year.

He worked out how plutonium behaves under pressure. That data was key to the device design.

What was the plutonium puzzle?

• Raja Ramanna recruited him in the autumn of 1969.
• His task was to study the equation of state of plutonium.
• That means how plutonium’s density changes with pressure and temperature.
• An implosion bomb needs this knowledge for its design.

What happened on test day?

• The test took place at 8:05 a.m. on 18 May 1974 at Pokhran, Rajasthan.
• It is known as “Smiling Buddha”.
• Its formal name was the “Peaceful Nuclear Explosive”.
• Ramanna led the team that developed the device.
• Chidambaram led the nuclear system design team.
• The plutonium came from the Cirus reactor at BARC.
• Homi Sethna chaired the Atomic Energy Commission after Vikram Sarabhai died in 1971.

What is the memory hook?

Think “Ramanna leads, Chidambaram designs”. Each had a different role.

He ran BARC and then the Atomic Energy Commission (AEC). In 1998 he led the team behind the second test series.

Which posts did he hold?

• He became Director of BARC in 1990.
• He started the supercomputer programme there.
• He was Chairman of the AEC from 1993 to 2000.
• He was Secretary of the Department of Atomic Energy (DAE) in the same years.
• He chaired the Board of Governors of the International Atomic Energy Agency (IAEA) in 1994-95.

What was his role in 1998?

• He led the DAE team that designed the devices for the Pokhran-II tests.
• The tests were held in May 1998.
• The DRDO took part with the DAE.
• Nuclear power capacity grew sharply while he led the DAE.

What is the memory hook?

Think “90 BARC, 93 AEC, 98 tests”. Three dates tell his climb.

He advised the government on science from 2001 to 2018. He also chaired a cabinet science panel.

What was the post?

• The Principal Scientific Adviser (PSA) is the government’s top science adviser.
• The office was created in November 1999.
• A. P. J. Abdul Kalam was the first PSA, from November 1999 to November 2001.
• Chidambaram held the post from 2001 to 2018.
• He also chaired the Scientific Advisory Committee to the Cabinet.
• K. VijayRaghavan came after him.

What did he start?

• He chaired the high-level committee for the National Knowledge Network (NKN).
• NKN connects educational and research institutions across the country.
• He helped set up the Rural Technology Action Groups (RuTAG).
• He helped set up the Society for Electronic Transactions and Security (SETS), in Chennai.
• He helped nucleate a coal power technology called advanced ultra supercritical.

What is the memory hook?

Think “Kalam first, Chidambaram next”. The post passed from one to the other in 2001.

He won two Padma awards. He also wrote over 200 research papers.

What honours did he receive?

• He received the Padma Shri in 1975.
• He received the Padma Vibhushan in 1999.
• He held honorary doctorates from more than twenty universities.
• He won the C. V. Raman Medal of the Indian National Science Academy in 2013.

What about his research?

• He wrote more than 200 research papers in refereed journals.
• All of his research work was done in India.
• He served on the Executive Committee of the International Union of Crystallography from 1990 to 1999.
• The Wire called him the “Last Flag Bearer of Homi J. Bhabha’s Vision and Legacy”.

What is the memory hook?

Think “Shri 1975, Vibhushan 1999”. The second honour came 24 years later.

Four mix-ups come up again and again. Learn each pair.

What are the traps?

• Which test? Chidambaram worked on the 1974 test. He led the DAE team for the 1998 tests.
• Who led in 1974? Raja Ramanna led the device team. Sethna chaired the AEC then.
• Which Padma? The Padma Shri came in 1975. The Padma Vibhushan came in 1999.
• Which PSA? Kalam was first. Chidambaram came next.

How do you remember them?

Think “1974 design, 1998 lead”. Match each year to his role.

Several names connect to the 1974 test. Learn who did what.

Who else is linked to him?

• Anil Kakodkar was a member of the BARC team for the 1974 test.
• Raja Ramanna led that team.
• Homi Sethna chaired the AEC at the time of the test.

What is the memory hook?

Think “Ramanna, Sethna, Chidambaram, Kakodkar”. Each name links to the 1974 test.