Australia Telescope National Facility

V. Radhakrishnan, a major figure in the world of radio astronomy, passed away early in the morning of 3rd March 2011, in Bangalore, India. Rad, as he was widely known, grew up in Bangalore, taking a BSc. in physics at the Central College of the Mysore University - his only degree till an honorary doctorate from the University of Amsterdam in 1996. His early fascination for radios and motorcycles grew into a lifelong love and deep understanding of all kinds of gadgets and machines, Travelling widely from his early twenties, he joined the radio astronomy group at the Onsala observatory of the Chalmers Institute of Technology in 1955. The 21 cm line and fluent Swedish stayed with him all his life. The next stop was the Owens valley observatory of Caltech in 1958, where his basic work on polarized interferometry revealed the magnetic field of Jupiter and the rotation of its interior for the first time. This period also saw early work on combining emission and absorption of atomic hydrogen in the galaxy to infer spin temperature and optical depth. This grew to a major programme at the Parkes observatory of CSIRO Division of Radiophysics, (which he joined by sailing across the Atlantic and Pacific in 1964-65!). The detailed account of this work filled an entire volume of the Astrophysical Journal Supplement, and formed a strong observational underpinning for the idea of a multiphase interstellar medium. A classic paper measuring the polarization swing of the Vela pulsar, gave birth to the widely used magnetic pole model for pulsar radio emission. He always ensured full credit to his many collaborators, including the people who joined him in building the instruments that made the science possible.

In 1972 he accepted an invitation from the Raman Research Institute (RRI) Trust to return to India and head the RRI which was undergoing a revival. Under his leadership, the institute grew from essentially zero strength to establish successful programmes in radio astronomy and different branches of physics. He assembled, trained, and inspired a group which undertook many projects over more than three decades. These included the construction and use of a millimeter-wave dish and receivers, and major collaborations with the Indian Institute of Astrophysics in building and using two low frequency radio observatories at Gauribidanur and Mauritius, Rad enjoyed a very special relationship with the radio astronomy group of the Tata Institute of Fundamental Research, and strongly supported its Giant Metrewave Radio Telescope project in kind, with some critical front ends and backends being built at RRI. With his students and colleagues, he worked on many aspects of pulsars and the interstellar medium.

By personal example, searching questioning, and intense discussion, he strove to build a unique atmosphere in which theory, experiment, instrumentation and observation were not separated but pervaded by a common spirit. Astronomers all over the world held him in high regard and responded readily to his invitation to visit the Raman Institute, He delivered the IAU invited discourse on pulsars in the 1985 general assembly, the Milne lecture of the Oxford University (1987), and the Jansky lecture of the NRAO (2000). Rad was elected a foreign fellow of the US National Academy of Sciences, the Royal Swedish Academy. He served on advisory boards of major observatories in Australia, the Netherlands, and the US, as President of the URSI Commision on Radio Astronomy (1981-83), and as a Vice-President (1989-91) of the IAU

Starting from the 1990's, he took up building and flying microlight aircraft. In his last decade, he went back to the sea, building a twin-hulled sailboat of his own novel design. Well after his eightieth birthday, he sailed it to Oman, then back westwards to Malaysia, and had every intention of going all the way round. Rad leaves behind his wife Dominique and son Vivek who is married to Namrata, with two daughters Veda and Surya.

        Provided by Rajaram Nityananda and Miller Goss