Gopalan completed his BSc (Hons) in Physics from Madras University (1959), MSc in Nuclear Physics from Andhra University (1960) with first rank and PhD from the Indian Institute of Science, Bangalore (1966) under the supervision of Professor VS Venkatasubramanian. He worked as a post-doctoral Fellow (1966- 1969) with Professor GW Wetherill in UCLA, on the chronology of meteorites and the first batch of lunar samples. Gopalan retired as a Director's rank Scientist in 1998, and has continued his research since then as an Emeritus Scientist.

Academic and Research Achievements: Joining the Tata Institute of Fundamental Research, Mumbai on his return to India (1970), Gopalan initiated noble gas studies on meteorites and moon sample. He moved to the Physical Research Laboratory (PRL), Ahmedabad (1973) and switched over to geochronology of the continental crust in India. Building the necessary mass spectrometer for Rb-Sr dating, he discovered very primitive rocks in Rajasthan. He studied the nature of the subcontinental mantle as reflected by the Deccan volcanic rocks by collaborating with scientists from the Scripps Institution of Oceanography. He set up a modern stable isotope laboratory to focus on the paleoclimatic potential of tree rings and foraminifera. Gopalan also established the first facility in India for 39 Ar-40 Ar dating of rocks to show that the intense phase of the Deccan violcanism predated the catastrophic impact of a large meteorite, resulting in global mass extinction. He set up a state-of-the-art laboratory for geochronology at NGRI, Hyderabad and trained many young scientists to undertake Rb-Sr and Sm-Nd systematics in mantle-derived rocks. A notable achievement was the Sm-Nd dating of a recently fallen mantle, suggesting its formation within the first few million years of the solar system. He has guided eight students for their PhD.

Other Contributions: Gopalan's other contributions include: fabrication of an ion probe at PRL, to study pre-solar isotopic signatures in meterotites; development of a sensitive sniffer of helium in soil gases as a geophysical probe of subsurface features; and establishment of the first Accelerator Mass Spectrometer for radiocarbon dating in the Institute of Physics, Bhubaneswar. Gopalan has helped in the establishment of mass spectrometer related facilities for Earth Sciences in many laboratories in India. He has served in the Editorial Boards of several journals and many scientific committees.

Awards and Honours: Dr Gopalan is a recipient of Fulbright Fellowship (1966), Krishnan Gold Medal of the Indian Geophysical Union (1982) and SS Bhatnagar Prize (1982). He is a Fellow of the Indian Academy of Sciences, Bangalore (1982), National Academy of Sciences (India), Allahabad (1990) and Indian Geophysical Union (1988). He has also received the Medal of Honour of the Indian Society for Mass Spectrometry (1991).