Govind Swarup: Pioneer radio astronomer, beacon of frugal science

Besides world class telescopes and institutions, his legacy of breathless inspiration will live on.

Somak Raychaudhury*

doi:10.1038/nindia.2020.134 Published online 9 September 2020

Govind Swarup (23 March 1929 to 7 September 2020) with children.

© TIFR Archives

Govind Swarup, who passed away on 7 September 2020 at 91, was a pioneer not just in radio astronomy but also in heralding an era of frugal science and in building robust institutions that post Independence India so yearned for.

With a larger-than-life personality and extraordinary ideas, he created world-class scientific facilities of the kind that India had not seen before. He built unique astronomy instruments from scratch and inspired people around him to dream of the impossible, and to achieve them.

Educated at Allahabad University in the early 1950s, Swarup worked at the National Physical Laboratory in Delhi with electronic parts gleaned from leftover radar equipment used in the Second World War. With his teacher K S Krishnan, he began measuring the 'spin resonance of the electron' at three centimetre  —considered a hot topic in physics at the time. This was the first sign of the unbridled innovation that became the hallmark of the “Swarup brand”. If India is known for jugaad or frugal innovation, Govind Swarup was its embodiment.

After a couple of years of learning to build a radio array to study the Sun with Australian radio physicist Joseph Pawsey at Potts Hill in New South Wales, Swarup ended up at Stanford University in California, US. He worked on a doctoral thesis with pioneering radio astronomer Ron Bracewell. In between, he worked at the Harvard Radio Astronomy Station at Fort Davis, Texas setting up a radio array for the Sun.. Stanford University wanted him for its faculty, but Swarup had other ideas.

Even half a century later, over a cup of tea, Swarup loved talking dreamily about how he, along with three other Indian radio astronomers in the US, wrote to Indian institutions to set up radio astronomy facilities in India. A positive response from Homi Bhabha, Indian nuclear physicist and founding director of the Tata Institute of Fundamental Research (TIFR), led  to the establishment of a unique radio astronomy group at TIFR.

Following an initial experiment at Kalyan, near Bombay (now Mumbai), with antennae shipped from Potts Hill, Swarup and his group found a suitable hill slope of near Ooty in Tamil Nadu. Here he built his first unique giant telescope — a parabolic cylinder half a kilometer long and 30 metre wide, on the natural Equatorial mount such that the rotation of Earth could help track celestial sources. 

Swarup also chose 327 MHz as the operating frequency — a range of radio waves that had not been well studied before. He built his monolith with material sourced from India and with help from a small team of dedicated students and engineers. Some of the measurements of the counts of radio sources he made with colleague V. K. Kapahi at the Ooty Radio Telescope (ORT) went on to provide strong support to the Big Bang theory of cosmology. Built in 1969, this telescope is still operational with numerous discoveries of pulsars, quasars and gravitational lenses to its credit.

The Ooty telescope did not just put India on the world map of astronomy, it produced a confident and ingenuous bunch of young engineers and scientists. Inspired by this visionary who came up with an idea a minute, this young crop was ready to take up any challenge. Moving base to Pune, they started building the largest radio telescope array in the world — thirty 45 metre lightweight wire-mesh dishes, spread over 30 km of vineyard territory along the Pune-Nashik highway.  Operating at frequencies as low as 150 MHz, the array was looking to find the spin-flip transition of hydrogen at distances as far away as 90 per cent to the edge of the Universe.

This mammoth contraption — the Giant Metrewave Radio Telescope (GMRT) — has been one of the top astronomical facilities of the world for two decades now, studying all sorts of sources from planets, stars to radio galaxies and supermassive black holes. Observers from all over the world compete for time on this facility, mostly over-subscribed by thrice its capacity. It has also been a  pathfinder for the Square Kilometer Array, an international effort to build the world’s largest radio telescope — the next big thing in radio astronomy.

Govind Swarup near one of the GMRT antennas in 1999.

© TIFR Archives

Swarup envisioned other kinds of institutions too. He was a firm believer of research as a way of learning, and was uncomfortable that in India students do not get to do original research till they are put through four to five years of strictly bounded training. With V. G. Bhide, the then Vice-Chancellor of Pune University, his ideas led to the establishment of today's Indian Institutes of Science Education and Research (IISERs).

Govind Swarup won many accolades in his life — the Shanti Swarup Bhatnagar award, the Padma Shri, the Grote Reber award and the Fellowship of the Royal Society, to name a few. But his greatest reward seemed to be in mentoring generations of peers and young students. He was very generous with his time and ideas. I cannot recall a single conversation with him when he was not excited about at least three new things, and in no time everyone around him would be talking about those things.

Along with his telescopes and institutions, Govind Swarup’s lasting legacy would be that breathless and infectious inspiration. A hundred years from now, he will be remembered as the 'Man who Had All the Ideas', and knew how to make them real.

(*Somak Raychaudhury is the Director of the Inter-University Centre for Astronomy and Astrophysics in Pune, India.)