Celebrating Women in Science: Meet Lucy Oswald, our new pulsars researcher

To mark International Day of Women and Girls in Science, we sit down with Lucy Oswald, our new Assistant Professor in Data‑Driven Radio Astronomy.

Lucy’s research focuses on pulsars, the enigmatic neutron stars famously discovered in Cambridge by Professor Dame Jocelyn Bell Burnell. Now, Lucy finds herself at the very heart of these groundbreaking discoveries, continuing that legacy and forging a path for future generations.

In this interview, she discusses her research, balancing academic life, perspectives on gender in astrophysics, the importance of mentorship, and her advice for aspiring scientists.

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Can you tell us who you are and what you work on?

Lucy Oswald: I’m an Assistant Professor in Data‑Driven Radio Astronomy at the University of Cambridge. And the clue to what I work on is in the two parts of that title: the data‑driven side and the radio astronomy side.

I study pulsars, which are neutron stars that emit beams of radio waves. They were discovered over half a century ago, and we still don’t really understand how or why they produce those beams.

Part of my work is about studying that emission directly, by observing as many pulsars as possible and looking for trends in their behaviour. The other part is using pulsars as tools, because their radio waves travel through the Milky Way and interact with things like dust, plasma and magnetic fields. That lets us build up maps of parts of the galaxy that we otherwise wouldn’t be able to see. It’s a lot of detective work, and it’s a lot of fun.

What first drew you to astrophysics, and why pulsars specifically?

I think it was a combination of things. One was just the excitement of astrophysics: the big open questions, trying to understand space and the extremes of what’s possible. The other was that as I studied physics, I realised that what I really enjoyed was the computational side: playing with data, extracting trends, looking at statistics.

Those two things came together quite naturally in astrophysics. I did some undergraduate projects on galaxies, but I actually came to pulsars almost by chance, during a PhD interview. We ended up discussing a pulsar paper, and I found the conversation so interesting that I ended up asking if my interviewer was offering a PhD project.

The pulsar research field is so dynamic and there is such a wide range of things you can investigate with them – there will be a connection to just about every area of physics you can think of!

I barely knew about pulsars during my undergraduate degree, but once that opportunity appeared, I thought, right, this is the thing for me, and I’ve never regretted it.

What does “big data” actually look like in pulsar astronomy?

I feel quite privileged, actually, because I’ve seen this growth happen in real time. In my first PhD project I studied one pulsar. Then it became two, then eighty‑four, then around three hundred. Now I’m part of a project called the Thousand Pulsar Array, where we monitor hundreds of pulsars every single month.

The data are big in lots of different ways. We’re looking at many pulsars, we’re observing them repeatedly over time, and within each observation you have huge numbers of individual pulses. Each pulse can look different, and then on top of that you’re observing across many radio frequencies.

So it’s not just the quantity of data, it’s also the number of dimensions of that data set, which means that there are many different avenues to explore.

What kind of techniques are needed to work with that scale of data?

There are two components to working with large data sets. One is data collection, and the other is data analysis. On the collection side, new telescopes like MeerKAT, which came live around 2018-2019, have completely changed the game in terms of how many pulsars we can observe and the quality of the data we can collect. Handling this influx of information requires big computers, lots of storage, and big collaborations.

Then there’s the question of how you actually get science out of all that data. My work increasingly focuses on large‑scale statistics rather than individual objects, and we’re also moving more and more towards machine‑learning approaches.

It’s about letting patterns emerge from the data itself, rather than relying only on what an individual researcher expects to see.

What’s the research question you’re most obsessed with right now?

The big questions I’m currently trying to answer are: Why is pulsar radio emission time-variable, and how does the pulsar magnetic field evolve over its lifetime?

I’m particularly interested in using the polarisation of pulsar radio emission to answer these questions, because it gives you direct information about the magnetic fields around the neutron star, which makes it an exciting diagnostic tool.

Advancing our understanding of pulsar physics enables us to push the boundaries of the laws of physics at the extremes – densities, magnetic fields, temperatures – and it also affects how well we can use pulsars as tools, for things like studying the Galaxy or even searching for gravitational waves.

Will new telescopes like the Square Kilometre Array (SKA) help with that?

Definitely. MeerKAT will soon become part of SKA‑Mid, which, together with SKA‑Low in Australia will give us the best sensitivity on the sky we’ve ever had. That means more pulsars will be discovered and we’ll be able to collect much higher‑quality data.

For the kind of studies I do, looking at polarisation and time-variability, we’ll be able to resolve that information in much richer detail, and for many more pulsars. I’m actively involved in preparing for science with the SKA because I think it’s going to be transformational.

How do you balance big‑picture curiosity with the realities of research: grants application, timelines, admin?

I’m learning more and more how important prioritisation is. That means being really careful about how you spend your time and focusing on what actually matters.

It also means being realistic. You start with these huge, blue‑sky questions, but then you have to ask: what can I actually answer with the resources I have right now?

If you’re clear about that, it gives you more flexibility later when things inevitably evolve and change because, and it’s the great joy of research, they always do!

How do you know when something isn’t worth pursuing further in research?

A lot of it comes down to how well you define the question at the start. If you’re too open, too vague, it’s very easy to get pulled down an interesting but ultimately unhelpful path.

There’s also knowing when to stop. You can always keep pulling on a thread, but if it’s not advancing the main question—or if you realise the data just aren’t good enough—it might be better to stop, change data sets, or adjust the question. That’s something one really learns through experience and trial and error, and that one continues to work on and improve over time.

What are you most looking forward to as you move fully to Cambridge?

Cambridge has a real strength in radio astronomy, going right back to the foundations of Cavendish Astrophysics. For me, coming in with a strong data analysis background, it’s exciting to be surrounded by people who work on instrumentation and who approach the data in different ways.

There’s also just an incredible breadth of research across physics and astrophysics at Cambridge, and I’ve already had lots of conversations that I’m keen to take forward once I’m there full‑time.

What does a great week look like for you?

It’s an interesting moment to be asking me that because as I just joined Cambridge I also just came back from maternity leave. So, the ways in which I’m currently doing things are very different from how I’ve ever done them before, and having a more structured day is now essential.

But I would say that for me a great week looks like a good balance of mentoring students, teaching, meetings with collaborators, and protected blocks of time for deep research: reading, analysis, and writing.

When you’re stuck on a problem, how do you reset?

I step away. I go for a walk or spend time with my baby. Anything that gets you thinking about something completely different. When you come back, you often realise the problem isn’t quite as hard as it felt at first.

How would you describe the current landscape for women in astrophysics?

There’s still a gender imbalance, but astrophysics is generally more balanced than some other areas of physics. I’ve always found it a welcoming and friendly environment, and I’ve never really felt that being a woman was an issue day‑to‑day personally. But I try not to comment on generalities based on my own personal experiences – it’s much more instructive to consider large-scale trends and notice which people are absent from the community.

The biggest change for me recently has been having a child and taking maternity leave. Research timelines don’t stop, and that can be challenging. I was fortunate to have lots of support and flexibility, but I never fully left work, even though I was officially on maternity leave.

I’m very aware that this can have wider systemic effects, particularly for early‑career researchers, and that this is going to predominantly impact women. This is not specific to astrophysics or even physics, it’s a wider research issue.

What can departments or research groups do better to support women, especially early in their careers?

Flexible working and supportive parental policies are really important, and I think employers in academia are generally doing well on that front currently. There are also positive moves like narrative CVs, which allow people to explain their career paths more holistically.

That said, it’s a complex issue, and no single change fixes everything. Awareness and willingness to adapt make a big difference.

Have mentors or role models made a decisive difference for you?

Yes, absolutely. My PhD supervisor, Aris Karastergiou, and a close collaborator, Simon Johnston, were incredibly supportive. Early on, they made it clear that no question was a silly question, which gave me the confidence to explore ideas properly.

I’d also mention Professor Dame Jocelyn Bell Burnell. I was very lucky to get to know her during my PhD, and she’s been a fantastic source of advice, perspective and common sense. She’s an extraordinary role model.

To conclude, what would you say to a girl who loves space but doesn’t feel she belongs in physics?

I think physics, and especially astrophysics, is often seen as very technical or very mathematical, and of course maths is part of it. But at its heart, it’s incredibly creative.

You’re thinking about possibilities, asking what if, coming up with ideas about how the universe might work. If you’re excited and curious, that’s what matters. You don’t have to fit a stereotype. Most people in the field are there simply because they’re fascinated by the questions.

 

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To learn more about Lucy’s research, visit her website.