International Women's Day 2017
For International Women's Day let us stand in solidarity with all the women of the world, celebrate their achievements, and work in whatever way we can to put an end to the patriarchy. Let us bear in mind that this day began as International Working Women's Day, in memory of the International Ladies Garment Worker's Union strike. The world runs disproportionately on the paid and unpaid labour of women, and including domestic and emotional labour, without equality in pay or conditions. Today and every other day let us be aware of this and act rightly.
In honour of all these things, today I'd like to write some things about a woman I admire, whose story illustrates so much of the spirit of this day. I am relying mostly on memory of Miller Goss' fabulous biography of her, Making Waves, which he kindly gave me in 2013 and which first made me aware of this marvellous person; on my understanding of the published scientific literature of her time; and a few brief biographies available online; so please forgive me if I make any factual mistakes in the following.
Ruby Payne-Scott (1912-1981) was a pioneer of radio astronomy in Australia and a bloody hero in my view. It is often said that she was the first female radio astronomer, but I think this rather undersells her achievement - she was not far off being the first radio astronomer at all. Although the field was initiated by Karl Jansky's 1933 discovery of radio emission from the Milky Way, it was not until better technology was developed for radar in the Second World War that the field properly took off, and Payne-Scott was one of a number of radar experts who in 1945-46 independently and simultaneously turned their swords into ploughshares and started observing the sky with their new hardware.
But let's backtrack. Payne-Scott attended Cleveland Street Girls and Sydney Girls High School, where she excelled. Entering the University of Sydney, she studied physics, winning the Deas-Thompson Scholarship, the School of Physics' highest prize. (Her name is inscribed on the honour roll in the entrance hall to the School, with a few other familiar names!) At that point in time, the University of Sydney (and Australian universities in general) did not offer PhD degrees, and similarly talented contemporaries such as Joseph Pawsey, her future collaborator, studied at Oxford and Cambridge for their PhDs; this option was not available to Payne-Scott, and she remained at Sydney to do a research masters. (Her Honours and Masters projects were both published in Nature, so I suspect she would have done a very good PhD indeed if she'd had the opportunity to do so).
After graduating, she taught briefly in Adelaide before working for AWA in Sydney, where she was given the role of librarian. (Imagine what kind of towering sexism would make you hire someone with two Nature papers under her belt as an administrator rather than as technical staff!) Fortunately, her talent was quickly recognized and she was moved to a technical position. In 1941 she began to work at the Council for Scientific and Industrial Research (CSIR), the predecessor of CSIRO, to work on radar in a technical role, becoming the radiophysics group's first female member.
During the Second World War, she contributed significantly to radar engineering in Australia. (It is a little-known fact that Mark Oliphant, the Australian lead of the Birmingham group developing the British radar system, left Britain during the war and set up manufacturing and research groups in his native Melbourne and then in Sydney. The CSIR and Defence radar technicians would make many significant innovations to Allied radar engineering and production independently of their British and American counterparts). One event during the War is particularly significant, however: at that time, the Australian public service required women to resign their positions upon getting married. She therefore married Bill Hall in secret in 1944, and her immediate superior Pawsey helped cover this up.
After the war, Payne-Scott made a series of discoveries and inventions that were absolutely foundational in astronomy. She was made aware of a discovery by the New Zealand Air Force that the Sun was a source of noise in radar equipment (remarkably, after initially publishing this, I learned that the intelligence officer and scientist who identified this was another pioneering woman, Elizabeth Alexander, head of the Radar Development Laboratory in Wellington!). In a remarkable series of experiments, Payne-Scott confirmed this, and discovered that in fact the Sun gives off radio noise in bursts of several different sorts (she personally discovered Type I and Type III solar radio bursts, and participated in work led by others others on Types II and IV!). That would be pretty good for most people. But she went above and beyond and made a truly significant innovation, that would form the dominant paradigm for radio technology since then. She was also involved in research with colleagues where they noticed that solar radio emissions correlated loosely with the presence or otherwise of sunspots, and began to think about how they could show that sunspots caused this radio emission. Unfortunately, the radio antennae available had extremely poor imaging capabilities, and could not deliver the required resolution to distinguish features on the solar surface.
The CSIR operated radar bases on the coast in and around Sydney, originally designed to look for incoming Japanese aircraft during the war. These of course are all east-facing - making them ideal for observing the Sun at dawn. What this also means, is that the radar picks up radio waves coming from the sun, and *also* radio signals reflected off the ocean. It is not clear to me whether Payne-Scott was aware of 1943-44 work by John Conrad Jaeger (Cambridge/CSIR/Tasmania), or (and I was quite surprised to learn about this) Fred Hoyle (then in the British radar team), who had both predicted this interference phenomenon, the radio analogue of the famous Lloyd's Mirror optical experiment, and had suggested using this to determine the altitude of incoming aircraft. (I imagine it is quite likely she was aware of Jaeger and not necessarily Hoyle). Remember, Payne-Scott's honours thesis was on precision spectroscopy and she had years of radio engineering under her belt; she uniquely made the connection between the interference pattern for the sea-cliff instrument, and the literature by Albert Michelson and his colleagues on using interference patterns like this in optical astronomy to measure the sizes of stars. (According to Goss' book, she was relied upon by her collaborators in particular as the team member with the best theoretical knowledge of optics and astronomy). Turning the Yagi antennae on the cliffs at Collaroy and at Dover Heights (near Bondi) to the Sun at dawn, she measured the interference pattern as the Sun rose; the Fourier transform of this, she realized, was related to the pattern of radio intensity from the Sun. The 85~m height of the Dover Heights cliff gives an interferometric baseline of 170~m; by the van Cittert-Zernike theorem, the longer the baseline you have, the higher the resolution you get. Taking this data, she laboured for weeks with a hand calculator to obtain a 1D image of the Sun in radio waves - the first such result - and compared this to an image taken at the same time in the optical from Mt Stromlo. The radio emission lined up with the positions of sunspots. The paper was published with as McCready, Pawsey and Payne-Scott; I'm not sure whether the author list was unfair, as the others made very significant contributions to what was a novel and technically challenging set of observations, and I'm not sure of the details of how the labour was divided, but it is certainly known from memoirs that Payne-Scott was the main theoretician on the paper.
This was huge: for the first time in radio astronomy, she recognized that interference patterns between multiple telescopes (in this case, the Yagi on the cliff and its virtual counterpart reflected in the ocean) could be used to recover high angular resolution images of astronomical objects, and she provided the first technology that could be used to achieve this. A flurry of work soon followed, of which the most significant was Martin Ryle's innovation (at the Cavendish in Cambridge) of using two separate telescopes with an electronic correlator, which is much more flexible and is the standard architecture for essentially all radio imaging equipement to this day. Ryle's paper on this cites the McCready et al paper as its main inspiration. Payne-Scott and the CSIR team were no slouches, and they very quickly adopted Ryle's correlator design, making a succession of instruments of their own with various technical improvements and publishing a series of papers on engineering aspects and astronomical observations. Payne-Scott is the lead author of several of these papers. Ryle won the Nobel in 1974 for the development of radio interferometry, and Ryle absolutely deserved it, for developing the radio correlator and for his indisputably great achievements in the first decades of radio astronomy science as well - but I really think it should have been shared with Payne-Scott, and probably Pawsey too, and I can't help but feel that if Payne-Scott had been a man, and they'd been at Cambridge rather than Sydney, this would have happened. (As it turned out, Ryle did share the Nobel Prize - with Anthony Hewish, for "his" discovery of pulsars. So Payne-Scott was passed over for a Nobel in the same year as Jocelyn Bell Burnell, which surely makes it a uniquely appalling year in the history of the Nobels.)
Life is not a Greek tragedy, and the premature end of Payne-Scott's career is entirely due to the small-minded bigotry of the men who ran CSIRO. When Payne-Scott became pregnant in 1951, it was, as you can imagine, much harder to keep the issue of her marriage under wraps, leading to a conflict between Payne-Scott, backed up by Pawsey, and the director of the CSIRO, Ian Clunies Ross. Payne-Scott objected that
"Personally I feel no legal or moral obligation to have taken any other action than I have in making my marriage known… the present procedure with regard to married women… seems to go far beyond the simple statement in the Act … [it] is ridiculous and can lead to ridiculous results."
She didn't win. She was eventually sacked by Clunies Ross and there wasn't a damn thing she or any of her allies in CSIRO could do about it. There isn't a happy ending to this story: she worked for the rest of her career as a maths teacher in Oatley, which she reportedly hated. What a bloody waste. What a disgrace to Australia it is that we treated her this way. (Let's also remember that similar dismissals happened to thousands of other women across the country until the law's reform in 1966. Shame.) She sadly suffered dementia and passed away at the age of 69. A nice coda, if there can be one to a story like that, is that her daughter Fiona Hall became one of Australia's most celebrated sculptors (an example of her work is the Folly for Mrs Macquarie, in the Botanic Gardens, Sydney, a memorial to the violence of colonization), while her son Peter became a prominent professor of mathematics .
There's a lot of stories about women in science who are martyrs to the cause, and I know it's been said that we should stop framing our narratives about historical women in science in just these terms. So I want to maybe look at this story from a few other angles. Ruby Payne-Scott was not just a martyr, but an activist who understood the sources of her oppression and raised consciousness in others about it. She was fiercely political, and was subject not merely to impersonal discrimination as a woman but explicitly targeted by security services as a dissident. She was a member of the Communist Party, and a feminist activist identified by ASIO as a follower of Jessie Street (hurrah!). She famously didn't hold back from expressing her political opinions, and scandalized conservative society with her penchant for wearing shorts and short-sleeved shirts like one of the blokes (and you bloody would too if you're working outdoors in the Australian summer!) So, I conjecture that through her deliberate actions, campaigning, and living according to her principles, which were famous in the community at the time, she must have had a significant influence on advancing the inclusion and liberation of subsequent women in Australian physics.
The other thing is, I think that the loneliness of martyrdom and the talent unrecognized is an easy trope when discussing people like this, and it doesn't fit Payne-Scott. She was well-liked by many of her contemporaries, and the ones who didn't like her found her abrasive and intimidating, which I think says more about them than about her. She worked well in a team, and while I want to absolutely highlight her singular achievement in the sea-cliff interferometer idea, execution and planning, most of her published research is in collaboration, particularly with Pawsey. She was known both as an excellent engineer, but also as arguably the most talented theorist in the division, and her ideas on optical theory put her in a position to suggest new experiments best done by specialists in other technologies. The best science is done when you have a team of people who get along with each other and treat one another with respect, and reject discrimination. Women's rights require women's rights at work, and work is not always remunerated. Remember that every single day and especially today.
If you're a bloke and you've read this far, here, have a role-model too: be Pawsey. Listen to women and collaborate with female scientists. Cite their work, and if you're in a position to, promote them and give them the resources they need to execute their ideas. Pawsey was humble and didn't take credit for his juniors' ideas, instead nurturing younger scientists and helping bring out the best in people. Pawsey intervened to promote Payne-Scott in the technical staff against opposition, and for years pushed back against and found ways around discriminatory rules that held her back. He doesn't need a pat on the back for this, it's no more than the decent thing to do and it's the bare minimum that should be expected of anyone in a position to help. Just don't be the bloody patriarchy. Don't be the bastards who held her back.
I wager it's probably due to Payne-Scott that I'm doing what I'm doing today. I don't really doubt that if Payne-Scott hadn't come along, within a few years, though not necessarily quite as soon as actually happened, Ryle, or Hoyle, or Pawsey, or Alexander, or who knows who else would have hit upon her ideas independently. But they didn't. The CSIR group had a head start thanks to her insight, and for a good while there it was just Sydney and Cambridge in the field, joined soon by Manchester, madly grabbing all the low-hanging fruit in what must have been just the most incredible time to be alive and be a scientist in a world that had just beaten fascism and was looking to the stars. This head start in Sydney put the CSIRO in the position to develop the Potts Hill, Narrabri, Molonglo and Parkes observatories in short order, and solidify Australia's position in the new field. (I note that in Fred Hoyle's 1957 novel The Black Cloud, astronomy institutions mentioned by name are Cambridge, Oxford, Heidelberg, Caltech - and Sydney). Not only that, in 1952, optical experiments by Hanbury Brown in Manchester based on trying to answer questions posed by Payne-Scott's research revealed surprising intensity correlations that flew in the face of quantum-mechanical wisdom. The Hanbury Brown and Twiss effect became the basis for Roy Glauber's Nobel Prize-winning reformulation of the quantum theory of optics, and it also led Hanbury Brown to come to Sydney in the 1960's to set up the first optical interferometer since Michelson's 1920s experiments, drawing on the existing expertise in radio interferometry. This led to the revival in the field, inspiring Antoine Labeyrie's experiments that established optical interferometry as a real astronomical technique. So my own research, on optical interferometry theory and experiment, is indirectly descended from Payne-Scott's realization in 1946, and the reason I learned about this remarkable body of theory was because Sydney University was the place that so much of it was developed - thanks to Payne-Scott again. I reckon without Payne-Scott, that might actually have never happened, and Australian physics would be immeasurably poorer. She made it through to her successes by the skin of her teeth in the face of discrimination, and I can only wonder at the people just as good as her who were a bit less lucky and what Australia has lost as a result. All of us from the University of Sydney have had her legacy to draw on and what a legacy it is.