Star scientist
Margaret Burbidge (1919-2020), one of the greatest astronomers of the 20th century and a pioneering observational astronomer, died aged 100
on April 5 in San Francisco, California, U.S.
THE year was 1961, the location Cambridge University. I was amongst the dozen or so research students in the Department of Applied Mathematics and Theoretical Physics (DAMTP). All of us, students and faculty members belonging to DAMTP, had been given “desk space” on two floors of the Phoenix building of the famous Cavendish Laboratory. Naming the building “Phoenix” was a tongue-in-cheek exercise by the Head of the DAMTP because the building had been rebuilt after it was burnt down.
It was one of those afternoons when we were busy with academic jobs like writing papers, having discussions, or reading research journals or simply gossiping. In my office, shared with two other students, we often talked about anything under or over the sun. The discussion was, however, interrupted by the entry of a senior scientist, Roger Tayler, who was evidently very excited—certainly not in the “cool” state one associates with an Englishman. What had caused the excitement?
It was like telling a pop music fan that the Beatles were out there, or a cricket lover that Don Bradman was in the corridor outside. “I want to tell you people, that the Burbidges are out there,” said Roger. He could hardly contain his excitement. And I recall (even today) the thrill I felt on that announcement. Certainly, I did not want to miss them! And it came as a great satisfied feeling to me when a few minutes later, the celebrated couple walked into my (one-third of an) office.
To understand the excitement generated that day by the arrival of the “Burbidges”, Geoffrey and Margaret Burbidge, often shortened to “B2”, it is necessary to appreciate the work they are often credited with.
So what was the reason for such accolades? To understand the contributions of Margaret Burbidge, we take a look at her early work. She did her doctorate work in the University of London Observatory in 1944 at the height of the Second World War. This meant going to Mill Hill Park from her residence in Hampstead Heath at night while the Luftwaffe was firing flying bombs from Northern France. On one occasion, the bomb exploded with such ferocity that all her telescope settings were disturbed.
In postwar peace times, the working was not so chaotic. But there were other problems. Her application for observing on the 100inch Mount Wilson Telescope in Southern California was turned down because the facilities in the observatory did not have women’s toi
lets. Margaret Burbidge got married to another up-and-coming astronomer, Geoffrey Burbidge, and both shifted their centre of activity to the United States. In 1957, the Burbidges combined with the duo of William Fowler and Fred Hoyle and the outcome was a comprehensive paper in Reviews of Modern Physics describing details of how different chemical elements are formed in stars. Nearly a 100-page paper, it covered a large number of scenarios which they used to show that except for some light nuclei like deuterium, most nuclei are produced in thermonuclear reactions in evolving stars. This work is often referred to as B2FH after the names of the four authors.
The husband-wife combination worked well for astronomy since
Margaret was an observer and instrumentalist while Geoffrey was a theoretician. Their styles also greatly contrasted. Geoff was aggressive while Margaret was gentle but firm and stuck to her point of view. In fact, many opponents in a controversy discovered that the soft-spoken lady was hard to budge on the basis of evidence submitted.
Margaret had been to India sev
eral times. Indeed, one could say that Bangalore and Pune were her favourite haunts. She had been a participant in a workshop conducted by the Inter-university Centre for Astronomy and Astrophysics (IUCAA) at Pune. The workshop had important inputs in observations and instrumentation, which helped guide future developments in these fields. Later Margaret became one of the after. It is said that Geoffrey shifted to astronomy influenced by Margaret’s passion and knowledge of astronomy and stellar spectroscopy, which subsequently grew into many long years of fruitful collaboration, yielding highly productive astronomy research, with her skilful observational data giving a firm theoretical basis to Geoffrey’s insights as Narlikar has recounted in his essay.
Their seminal work on Alpha2 Canumvenaticorum (a type of variable star), which was published in 1955, drew the attention of the U.S. nuclear physicist William Fowler, who was then visiting Fred Hoyle at Cambridge. Between 1946 and 1954, Hoyle had advanced his theory of stellar nucleosynthesis of how nuclear fusion reactions of hydrogen and helium in the stars drive the formation all the heavy elements in the stars. The Burbidges’ spectroscopy results were seen as a means to verify Hoyle’s hypothesis. This led to the collaboration among these four, which resulted in the magnum opus landmark paper, universally referred to as the B2FH paper, to which Narlikar has referred.
In her interview for the Oral History Archives, when asked as to which piece of research that she had done had given more satisfaction than anything else, Margaret Burbidge said: “Oh yes. It would be the nucleosynthesis, B2FH.”
On Fowler’s advice and invitation, the Burbidges moved to California and in 1962 they moved to the University of California in San prestigious honorary fellows of IUCAA. Another contribution to IUCAA programmes was her participation in science popularisation activities. At the conclusion of her opening lecture, she showed a group of geese all going in one way with a small group in the lead. She pointed out how anomalous evidence is ignored because it is found to be inconvenient for accepted paradigms.
Diego (UCSD), where Margaret Burbidge had unquestioned time on the Lick Observatory’s 3m telescope. After the discovery of quasars in 1963, she measured their spectra and by measuring their very large red shifts, she also showed that these were the most distant objects known until then.
Margaret Burbidge also measured the rotation and masses of spiral galaxies. Her skill at instrumentation, coupled with her observational experience with distant astronomical objects, resulted in her contributing to the development of the Faint Object Spectrograph (FOS), which was launched aboard the Hubble Space Telescope in 1990.
Vera Rubin, one of Margaret Burbidge’s collaborators in her galaxy rotation studies, would later discover motion in the far outskirts of spiral galaxies which could be explained only through the hypothesis of gravitational pull of unseen matter, now called “dark matter”. As the U.S. astronomer Virginia Trimble recently wrote in Nature, this was one of the many ways in which Margaret Burbidge blazed a trail for women astronomers.
Margaret Burbidge was not one to be deterred by setbacks and hurdles; she would always find a way to overcome it. In fact, in her tweet in 2017, when she was 97, she had said: “If you’re having troubles in your life, to quote myself—‘if you meet with a blockage, find a way around it.’ You can do it.”
With her many academic contributions, many honours came her way. She was made the Director of the Royal Greenwich Observatory (RGO) in 1972. Although this was a well-deserved honour, it was rightly criticised as it did not do honour to her. Why? Historically the directorship of the RGO carried with it the title “Astronomer Royal” (AR). From 1972 onwards it was decided to split the dual status and accordingly another (radio) astronomer, Sir Martin Ryle, was made the AR. It would instead have been better to give both the posts to the first appointee under the new rules. Thus Margaret Burbidge should have been the first AR as well as Director, RGO. Margaret, however, was not very happy with her RGO appointment because the work was more bureaucratic than she liked and the weather was not very conducive for her usual observing experience. So she resigned and came back to her earlier work in California.
Margaret Burbidge was awarded several distinguished prizes. One of them was the Henry Norris Russell Award, which requires delivering a lecture.
But she was sensitive to sexually discriminating awards. For example, she was offered the Annie Cannon Prize, which was for women only. She felt that such awards tried to distinguish between men and women and could create the undesirable impression that one gender was superior to the other. Nevertheless, she kept fighting for the equality of men and women.
Margaret Burbidge belongs to the “old style” of astronomers whose genre is fast disappearing. In the earlier days the observer had to use a series of tests to decide if an existing theory was right or wrong. Modern observers start with the assumption that their paradigm is correct and the telescope is there to rubber-stamp that belief.
Young or old, we all will miss her.m Jayant Narlikar is Emeritus Professor, Inter-university Centre for Astronomy and Astrophysics, Pune, and founder director of the centre.