The Universe in Radio Vision

The Universe in Radio Vision

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Carol Sutton Lewis: In a career that lasted just six years, an Australian physicist named Ruby Payne-Scott helped lay the groundwork for a whole new type of astronomy—but to keep her job, she had to keep a pretty big secret.  Samia Bouzid brings us this story.

Samia Bouzid: In early February 1946, the sun let loose an enormous solar flare, sending an invisible burst of radio waves sweeping over the planet for days. It twisted the dials on ships' compasses, sent random ghostwritten messages through teletype machines, and blacked out radio communications between the U.S. and Europe.

For lots of people, it was a disaster. But for a team of physicists on the Australian coast… 

Miller Goss: A miracle occurred. 

Samia Bouzid: Radio astronomer, Miller Goss.

Miller Goss: The largest sunspot in the modern era began on the sun. That's one of the major coincidences of radio science in the 20th century.

Samia Bouzid: Because while radio waves were frying communication systems, they were also streaming onto a radio antenna on a seaside cliff in Sydney, Australia.  

It was the middle of summer, just before sunrise, still dark out. And there, standing on that cliff, Ruby Payne-Scott was studying the sky. Ruby hadn't been an astronomer for long. Actually, she might not have even called herself an astronomer at that moment. She'd spent the last few years focused on our planet and the Second World War. But with the war finally over, Ruby got to focus on some loftier things. And on that day on the cliff, she was making one of the most important observations of her career. 

A career that abruptly ended just a few years later. When she left astronomy forever at just 39 years old. But the work Ruby and her colleagues did that day and in the following years laid the groundwork for a whole new field of astronomy. One that would open a window into the universe and transform the way we explore it.

Carol Sutton Lewis: This is Lost Women of Science. I'm Carol Sutton Lewis, and today I'm joined by Samia Bouzid, who brings us the story of Ruby Payne-Scott.  Samia, back to you.

Samia Bouzid: Okay, so let’s go back to that clifftop in 1946, Ruby was doing something few people in the world had ever done at that time. She was observing radio waves from space. But just a few years earlier, Ruby wasn't thinking about space at all. 

In her late 20s and early 30s, Ruby was working at the University of Sydney, where every day she'd walk through a heavily guarded door into a building on campus known as the Radio Physics Lab. This was World War II and that name was actually a cover for what was really a highly important military operation. 

Ruby was one of the few women to walk through that door as a scientist, not an admin. There were hardly any women in physics back then. But, Ruby just had this habit of excelling at things that no one expected her to.

Sharon Bell: We're talking about someone who was born in 1912 in a country town in New South Wales, Australia. 

Samia Bouzid: Sharon Bell is an anthropologist and professor emerita at the Australian National University in Canberra. Much of her work focuses on women in science in Australia.

Sharon Bell: It was a very beautiful agricultural town, but in fact, at that time it must have been a very isolated place. It's not a town where at the time there was any tertiary education, no universities, no colleges...

Carol Sutton Lewis: Okay, no advanced education, no universities, no colleges. So, Samia, how does Ruby end up becoming a physicist in the 1940s?

Samia Bouzid: Well, we don't know too much about the family she grew up in, so we don't know how much they encouraged her or supported her education, but it seems like she just had this innate curiosity about the world. And you can see, if you look through newspaper archives from when she was just a kid, by elementary school, she was already racking up prizes and awards and getting written up in the local newspaper. 

And it just seems like she had this drive to learn. She ended up going to the University of Sydney to study physics. And then in 1936, she got a master's degree from there, which was the highest degree you could get in Australia at the time. 

In the 1930s, she spent a few years working in a cancer research lab on radiation treatment, which was fairly new at the time. But after the war started, she got that job at the radio physics lab. 

Her job was to work on a budding technology called RADAR. It stands for radio detection and ranging, and the British had been using it to detect warplanes. Radar kind of works like bat echolocation, which, is that a helpful comparison, Carol? Do you know how bat echolocation works?

Carol Sutton Lewis: No, I have to confess, I do not know how bat echolocation works. So please, enlighten me.

Samia Bouzid: So bats fly around in the dark, and a lot of times they use their ears instead of their eyes to navigate. So they send out these little pulses of sound that are really high pitched and that sound bounces off stuff. And depending on how long the sound takes to come back, they can tell how far away objects around them are. So the longer the sound takes to come back, the farther away the object is. Does that make sense so far?

Carol Sutton Lewis: Yep, got it.

Samia Bouzid: Okay, so radar is the exact same principle. It just uses radio waves instead of sound. And that can be helpful because radio waves travel at the speed of light, so they can do this much faster. And that means you can use them to detect objects that are much farther away. 

So you can see why the military might be interested in something like this. Because using radar, you can start detecting objects around you, even if you can't see them with your eyes. And that'll help you, say, fend off enemy warplanes coming to attack you in the middle of the night.

So the British had this new invention called radar, and they shared it with their ally, Australia, just before Australia joined the war. And there was no time to waste. Ruby was hired in August of 1941, and just months later, Japanese warplanes bombed Pearl Harbor. Which showed Australia just how vulnerable they were too. They did not want to be surprised like that. So, Ruby's job was to develop radar equipment and detect enemy aircraft, which involved a lot of complicated math. 

Miller Goss: Everybody realized that she was a real physicist, and it turned out that she was a fantastic mathematician. 

Samia Bouzid: Miller Goss is a radio astronomer and probably the world's foremost Ruby Payne-Scott expert. He's written an extremely in-depth biography about her. 

Miller Goss: I was told by people who worked with her in the first years of the war that her mathematical skills were admired by everyone. If they had a math problem, they would go to her. 

Samia Bouzid: And not only was she a fabulous mathematician and physicist, she was also a top-tier electrical engineer. So soon, her team had her doing a little bit of everything.

Miller Goss: She was very soon put into research work, building and modifying radars.

Samia Bouzid: Ruby was really good at her job, but there was no escaping the reality of her era. There were only two other female physicists working in her whole lab, and as much as her colleagues admired her, she had to fight for some very basic workplace rights. Like the right to wear shorts.

Miller Goss: Everybody was wearing shorts and this made a lot of sense. There’s no air conditioning, and she would climb up on ladders. And the librarian at the institute said, Oh, women are not allowed to wear shorts. And she said, "This is absurd. I'm climbing up a ladder. Men are all over the place. I'm not going to wear a dress."

Samia Bouzid: And that wasn't the only rule Ruby had a problem with.

Miller Goss: The other thing is, women were not allowed to smoke at work. Men were…

Samia Bouzid: …which didn't really affect Ruby because she wasn't a smoker, but it still made her mad. It was the principle of it. So she staged a one-woman protest.

Miller Goss: She once went to an interview and, uh, she pulled out a cigarette. She never smoked, but during the interview with the librarian, Ruby pretended that she was smoking. This was her rebellion. Maybe the only cigarette of her life.

Samia Bouzid: But one of Ruby's biggest acts of rebellion was a quieter one. In 1944, she got married secretly. Sharon Bell again.

Sharon Bell: At that time there was a marriage ban in place in the Australian Public Service for married women. So when women married in the Australian Commonwealth Public Service, it was deemed that they would no longer have permanent work in the organization. One has to take a deep breath because this is not ancient history. This is 1944. The marriage ban was not lifted in Australia until 1966. 

Samia Bouzid: And when Ruby first got hired, she wasn't married, but then she met Bill Hall. He was a friend from her bushwalking club, because when she wasn't helping defend her country from air raids, she'd go trekking through the Australian wilderness on days-long excursions. 

Bill came from a completely different social background. He was a rugged, outdoorsy man who had received very little education. Ruby, meanwhile, was obviously very well educated. But the two of them bonded over long walks, their love for the outdoors, and their left-wing politics. And in 1944, they got married. 

Carol Sutton Lewis: How sweet is that, but how could you keep something like that a secret?

Samia Bouzid: Yeah, well, according to Miller Goss, some people suggested that Ruby maybe wore her wedding ring on a necklace, and she kept her maiden name, and she just didn't say anything to her higher-ups, so it seems like her marriage might have been sort of an open secret among her closest colleagues, but they would have known what would happen if word got out, so they kept their mouths shut too. And for the time being, it worked. Ruby's marriage stayed a secret.

Carol Sytton Lewis: Let me just guess that men could be married, or was the marriage ban- was the marriage ban an equal opportunity marriage ban, or could men be married?

Samia Bouzid: You guessed correctly. That was a special rule for women.

Carol Sutton Lewis: Of course. Continue.

Samia Bouzid: Alright. Ruby's higher-ups had other things on their minds anyway. The war was coming to an end, so Australia's Council for Scientific and Industrial Research, CSIR, which ran the Radio Physics Lab, had to answer one big question. What's next? 

Here they had on their hands a bunch of the country's top physicists with a bunch of high tech equipment that they'd developed for the war. But as the threat of attack receded, those physicists and their wartime radar work were no longer needed. So the CSIR made a decision. 

Instead of setting all their best physicists loose, the CSIR held on to this team and set them on a new task: exploring radio waves coming from the sky. And just like that, these wartime physicists became astronomers. 

One of their first missions was to look into a weird thing that radar operators had encountered during the war. 

Every once in a while, they'd be slammed with a burst of radio waves that jammed up all their receivers. At first, they thought these bursts were coming from enemy forces because that was a thing that happened sometimes. But then, some people began to realize that there was a pattern to these bursts. They seemed to line up with the appearance of sunspots. 

Carol Sutton Lewis: So what are sunspots anyway, wait, let me guess. Spots on the sun.

Samia Bouzid: Yeah, I mean, if you look at pictures, they look like dark spots on the sun. And that's because they're cooler than everything around them, which, that happens because the sun is full of these magnetic field lines. And as the sun spins around, those lines get twisted up, and they can mess with the flow of energy around the sun. So you end up with some spots that are cooler than others. 

So that's what a sunspot is. It wasn't exactly obvious that these things should be spewing radio waves or anything like that. But Ruby's team confirmed people's suspicions. There was a strong correlation between the intensity of the radio signal and the amount of sunspot activity. The only thing was, their measurements weren't that precise. They just knew that the radio waves were coming from the general vicinity of the sun. They couldn't trace the signal back to the sunspots themselves. But that was about to change.

On January 26th, 1946, Ruby woke up while the sky was still black and went out to Dover Heights, a cliff that overlooked the ocean on the edge of Sydney. There was an old military radar station perched on that cliff with a big antenna. It kind of looked like the skeleton of a billboard you’d see driving down the highway. 

Now that the war was over, the Australian army had turned this station over to the radio astronomy team. And Ruby was there to observe the sunrise. She was standing on that cliff as the sky brightened in the east, looking out over the open ocean.

And just before the first visible rays of sunlight emerged, the first radio waves hit the detector. And Ruby saw something exciting: fringes.

Carol Sutton Lewis: What's that? What are fringes?

Samia Bouzid: So fringes are a really telltale kind of pattern that shows up when two waves overlap. So, you know how when you throw a pebble into a pond, it'll make ripples that spread outward?

Carol Sutton Lewis: Right. Mm hmm.

Samia Bouzid: So if you throw two pebbles, they'll make two sets of ripples, and those will eventually run into each other. And that pattern that they create when they intersect, when they run into each other, that's a fringe.

Carol Sutton Lewis: Ah.

Samia Bouzid: So another really common example is when you play two notes that are really close together and clash with each other a little bit. You'll actually hear what sounds like beats as those waves interfere with each other. So that's another kind of fringe pattern. Anyway, the big takeaway here is that to get a fringe pattern, you have to have more than one wave. It only happens when there are waves overlapping. 

So when Ruby saw fringes that morning, she realized she was looking at not one, but two signals hitting the detector. It was the first time she'd ever seen anything like that from the sun. But she realized what she was looking at right away, thanks to all her work with radar. 

Miller Goss: It had been discovered during the war if you pointed the radar close to the horizon and an airplane was coming, you would see these interference fringes. It's the interference between the direct ray, the ray coming from the airplane, and there's another ray that bounces off the sea.

Samia Bouzid: In other words, the sea acted like a giant mirror. Some radar waves would bounce off an airplane and come straight back to the detector, as expected. But some of them would bounce off an airplane, then reflect off the ocean, and then hit the detector. By the time these two sets of waves hit the detector, they were ever so slightly offset, so they interfered with each other and created fringes.

Ruby recognized this pattern. And she also realized this was a game changer. Because she could use some math to separate out the two interfering signals. Then she could triangulate to locate the source with a lot more precision.

This technique is called interferometry. During the war, radar operators had done this to pinpoint the location of planes, and now Ruby's team would be able to use the same technique to trace back the radio bursts to a precise spot on the sun. What Ruby didn't know that morning, as the sun came up over Dover Heights, was that this discovery had come just in time for one of the biggest moments of her career. 

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Samia Bouzid: Just days after Ruby stood on that cliff and measured the radio waves unleashed by the sun, a new cluster of sunspots sent radio waves sweeping over earth. This is what caused the geomagnetic storms that twisted all those compass needles and made teletype machines sputter gibberish. 

It wasn't enemies. It wasn't aliens. It was the sun. And in the midst of all of this, Ruby and her colleagues headed back to the cliffs to catch the culprit in the act.

Miller Goss: And it was so easy because you didn't have to have a big radio telescope to do this because of the intensity of these giant flares. Sunspots were so big and there was so much solar activity the radio intensity of the sun could change by a factor of 10 or 100 or even 1,000 in a couple of seconds. 

Samia Bouzid: Once again, Ruby and a few of her colleagues this time arrived just before sunrise. They only had about a one-hour window when the sun's rays would bounce off the ocean at just the right angle to create that interfering signal they were looking for. So as the sun came up, the team recorded the bursts as they streamed into their receiver. Later, they analyzed their data, and by combining information from the two interfering signals, Ruby and her team finally found the answer they were looking for. 

Elizabeth Mahony: That allowed her to pinpoint where the radio emission was coming from on the surface of the sun.

Samia Bouzid: Elizabeth Mahony is a radio astronomer working at Australia's National Science Agency, which is now called the CSIRO. 

Elizabeth Mahony: So they were able to say it's not just coming from the direction of the sun, she was able to deduce that it was coming from the sunspots.

Samia Bouzid: Back then, people didn't understand the exact mechanics of how this all worked, but Ruby's team had cracked the first key part, confirming where these waves were coming from. And you might think, okay, this is just a very niche finding that might interest a handful of astronomers. But it wasn't just that. It was a proof of concept for a whole new way of doing astronomy. 

It demonstrated the power of interferometry as a way of making precise observations of radio emissions from space. And today, many world-class radio observatories still use interferometry, it’s just instead of depending on the ocean to reflect a second signal, they combine the signals from multiple dishes in an array. 

In a way, it was the birth of modern radio astronomy. Before this point, astronomy meant pointing telescopes at the sky, looking at anything that shined. but traditional optical telescopes only pick up the kinds of light our eyes can see.

And it turned out, there was much more in the universe that wasn't visible to our eyes.

Miller Goss: Radio astronomy provided a new window on the universe. It turned out that the universe looked a lot different in the radio than the optical astronomers had known ever since Galileo in the 17th century.

Samia Bouzid: Over the next few years, Ruby and her colleagues charged ahead in this new field of radio astronomy, exploring the sun in ways that had never been possible before. They categorized different kinds of radio bursts and figured out how they were tied to different events on the sun. 

They also measured the temperature of the sun’s corona, the wispy atmosphere that surrounds the sun. And they found that it was incredibly hot. Far hotter than the fiery surface of the sun itself. We feel like we know the sun. I mean, we see it all the time. But Ruby and her team were finding out that there was a lot we didn't know. In those days, they were just making one discovery after another, thanks to radio astronomy.

Elizabeth Mahony: They created a whole new field of research. They became not only, you know, world leaders in Australia, but they helped Australia become one of the leading groups in radio astronomy.

Samia Bouzid: Ruby was shining in her career. She wasn't just the person running out to cliffs at dawn. She was also doing data analysis behind the scenes, basically turning those radio signals into something meaningful. 

And she was perfect for this, because she understood the engineering and the physics and the math. 

But personally, things weren't going as well. Shortly after the war Ruby got pregnant. But she suffered a miscarriage while she was at work. Some of what happened around this time has been lost to history, but years ago, Miller Goss spoke with some colleagues of Ruby's, and they told him that she was rushed to a hospital in the middle of a meeting.

Afterwards, Ruby's name vanished from meeting notes for almost a year. 

In 1947, she returned to work, but things were changing in her workplace. In 1949, the Australian government reversed a wartime policy that had raised women’s salaries. Ruby kept her salary for the time being, but for many women, that meant a salary cut of something like 15 to 25 percent. 

Ruby vehemently protested this ruling, but nothing changed. 

And soon, things got even worse for Ruby. In 1950, executives at Ruby's workplace discovered her secret marriage while going through some paperwork and she and the chairman had it out. In a letter, the chairman accused her of hiding pertinent information, and pressured her to reveal the date of the marriage. 

And here's what Ruby had to say about that: "Personally, I feel no legal or moral obligation to have taken any other action than I have in making my marriage known." The chairman wrote back, "There can, of course, be two opinions on that point, but I will content myself with pointing out that if everyone thought as you do, or acted as you apparently think proper, the administration of CSIRO would be greatly complicated, and we would have to introduce a system of rigid scrutiny of the actions of officers instead of relying on their discretion and good sense." 

Carol Sutton Lewis: He discovers that she's secretly married, he is chastising her for violating the terms of this ridiculous rule, and in response to her defending herself, he says, you violated the honor system? 

Samiaouzid: Right, essentially, he felt like there should be this honor system where she should have come to tell him she was married so she could get demoted.

Carol Sutton Lewis: Oh, sh–[laughs]

Samia Bouzid: But, anyway, in the end, Ruby lost. She lost the debate. She lost her job as a permanent employee. I mean, she was the first female radio astronomer, one of the pioneers of this whole new field. But she got demoted to a temporary position. And she lost her entire retirement fund. And in spite of all that, she still stayed for one more year. But in 1951, she couldn't stay any longer. 

Miller Goss: She gets pregnant for the second time. There is no maternity leave. It doesn't exist. The option is, if a woman was about to give birth, she quit her job. And that happened because her son, Peter, is about to be born later that year.

Samia Bouzid: So just six years after her radio astronomy career had begun, Ruby had no choice but to give up her job. And it seems like her colleagues knew what they were losing. At her farewell party the summer of 1951, her boss, Joe Pawsey, described her as the best physicist in the lab. 

And around the same time, the organization's CEO wrote her a letter, saying, “Unfortunately, we cannot give a married woman leave without pay, but I assure you that I, at least, would be very pleased to see  you return to radiophysics in due course.” Ruby never did come back to the Radiophysics Lab, though. She never returned to astronomy at all. 

Carol Sutton Lewis: Oh my goodness, give me a break. So, the CEO writes we can't give you any kind of leave from- a maternity leave. But, I would welcome you back to have a demoted job. No wonder she never went back to astronomy.

Samia Bouzid: Yeah, if women back then were allowed, or better yet, supported in having babies without giving up their jobs, it's possible Ruby's story would have ended differently. 

She might have unveiled even more secrets of the universe. Because after she left, her colleagues started looking way past the sun, deep into the galaxy and beyond. But Ruby didn't get to be part of this. 

And in some ways, her story is yet another example of a woman who is forced out of science because of sexist policies and a lack of support. But I called up Ruby's daughter, Fiona Hall. By the way, Fiona's actually a really successful sculptor living in Tasmania. And she told me she actually doesn't see her mother's story that way.

Fiona Hall: I really don't believe that she was forced to go. Both of my parents, you know, they really wanted children and so they wanted to, to be there for us and not to be, well, my mother didn't want to be, you know, like a working parent.

Samia Bouzid: Fiona was born just two years after her brother, when Ruby was 41. And now, with two young children and her career as an astronomer behind her, Ruby dove headlong into life as a mother.

Fiona Hall: It was a- an upbringing where we were both loved unconditionally.

Samia Bouzid: As a mother, Ruby introduced her kids to books and art and science. She and her husband took them for walks in the wilderness and to political protests to speak out against war. But she also let them follow their interests without too much pressure. 

And it seems like Ruby excelled at being a mother, just as she excelled at everything else she had ever put her mind to, because both Peter and Fiona ended up being extraordinarily successful people. Here's Sharon Bell again, the anthropologist.

Sharon Bell: Peter Hall, who, was an extraordinary statistician and mathematician and the American Statistical Association, in fact, said that he was one of the most influential and prolific theoretical statisticians in the history of the field.

Samia Bouzid: And then there's Fiona...

Sharon Bell: ... who is an extraordinary and well-known Australian artist, recognized internationally. So one can say as a mother, you know, she continued to contribute in terms of producing leaders in the field, and one of those in the field of mathematics. 

Samia Bouzid: Once Ruby's kids got a little older, Ruby got a job teaching math and science at a nearby girls school. She taught there for 11 years. Then in 1981, when she was 68 years old, Ruby died of dementia. By then it had been 30 years since Ruby left the field of astronomy, and she had mostly faded into history.

But the field she helped establish was flourishing. And today it still is. Around the world, astronomers have arrays of radio dishes that use interferometry to essentially do what Ruby was doing back in the day. Of course, it's more sophisticated now, but the basic idea is the same. They tease apart multiple signals, and then they put together the information from each signal to create one sharp image, just like Ruby's team did with their sea-cliff interferometer. In 1974, two radio astronomers who developed a technique for interferometry even won a Nobel Prize for the way their work broadened our view of the universe. 

Brian Schmidt: To my mind, it's unfortunate she did not share in that Nobel Prize, although I can understand, why it didn't, but, you know, she did that foundational insight that got it all going. 

Samia Bouzid: Brian Schmidt is an astronomer who won the 2011 Nobel Prize in Physics for helping discover the expansion of the universe is accelerating. He's also a big fan of Ruby Payne-Scott.

Brian Schmidt: I think if they, if that were happening today, she would have won a Nobel Prize. I mean, would have been very plausible for them to have done so. 

Samia Bouzid: Of course, that's all speculation, but it really is hard to overstate how radio astronomy changed our view of the universe. 

It's sort of like, imagine you were walking around the world and all you could see was blue and green, so looking at a forest you wouldn't see tree trunks or dirt, you'd just see leaves and grass and sky, and then imagine that all of a sudden the other colors became visible and looking at the same forest, you suddenly saw a brown deer and colorful woodpeckers and red fruit on trees. This is how dramatically Ruby and her colleagues changed our view of the universe. 

With radio vision, astronomers have discovered jets of radiation spewing from supermassive black holes. They've discovered the first light released in the universe. They've seen the birthplaces of stars, and dead stars that flash like lighthouses giving off beacons of radio light. 

Thanks to radio astronomy, and thanks to people like Ruby Payne-Scott, they've uncovered many of these strange and incredible things in what otherwise looks like darkness.

Carol Sutton Lewis: This episode of Lost Women of Science was hosted by me, Carol Sutton Lewis.

Samia Bouzid: And me, Samia Bouzid. I wrote, produced and sound-designed this episode with help from our senior producer, Elah Feder. Lizzie Younan composes all of our music. We had fact-checking help from Lexi Atiya.

Carol Sutton Lewis: Thanks to Jeff Delviscio at our publishing partner, Scientific American. Thanks also to executive producers Amy Scharf and Katie Hafner, as well as to senior managing producer, Deborah Unger.

Finally, thank you to the Borror Lab at the Ohio State University for allowing us to use their bat echolocation recordings.

Lost Women of Science is funded in part by the Alfred P. Sloan Foundation and the Anne Wojcicki Foundation. We're distributed by PRX.

Samia Bouzid: See you next time!