Professor Catherine Heymans: What is it that’s turning off children from different backgrounds from pursuing a career in science?

“Oh! We haven’t talked about JWST! You have to include the James Webb Space Telescope. The launch date has finally been announced for 18 December, so we are all going to be crossing our fingers up till Christmas. We’re going to have to be really well behaved so Santa sends us this present of JWST being launched.”

I’m halfway through interviewing Professor Catherine Heymans, the new Astronomer Royal for Scotland, when she breaks off to talk about the next big date in all astrophysicists’ calendars. Her excitement practically fizzles over the Zoom line. She’s a woman who absolutely adores her career.

“The James Webb Space Telescope is the next big space telescope. It has been in development for so long and it is going to be the biggest space telescope that we have and it is going to allow us to see the first stars and galaxies that were ever created in the universe. It’s going to be so exciting. So yeah, 18 December, the entire international astronomy community is going to be like this,” Heymans crosses her fingers, “because if it blows up on launch it’s a complete disaster.” She laughs.

Heymans is an easy woman to like. Her excitement about science and space is palpable, even for the bits she’s not involved in like the JWST. Her warmth and enthusiasm make her a natural fit for encouraging and persuading the next generation of scientists, a key part of being Astronomer Royal.

Heymans is also the first woman in the job. All 10 of her predecessors, dating back to 1834, have been men. “They were the founding fathers of astronomy. To follow in their footsteps is a great honour, but I think the word ‘father’ there is the keyword,” she says.

I’m very honored to have been given this title… just to start changing that cultural perception of what a physicist is, what an astronomer is, what a scientist is

It’s a ratio she is used to. When she studied physics as an undergraduate at the University of Edinburgh, around one in ten students were female. She was not taught by a single female lecturer until starting her PhD. While things have started to improve – around a quarter of physics students now are women – change is slow.

“Why is that? There are so many different ideas of how to answer that question, but I think at the core of it is, it’s cultural,” suggests Heymans. “It’s not just astrophysics that has a gender imbalance. There are all sorts of jobs that have gender imbalance and there’s this cultural perception of who does a certain job. Our kids learn that. It’s unconscious bias of who does what job and it’s kind of hard to change that.

“That’s why I’m very honoured to have been given this title, so I can show people just one example of someone who is different from what you might expect a physicist to look like, just to start changing that cultural perception of what a physicist is, what an astronomer is, what a scientist is.”

She’s keen to play a role not just in increasing the number of women in science but to broaden the diversity of the field overall.

“The gender imbalance is nothing compared to people from non-white backgrounds. That is something we really genuinely have to start addressing. What is it that’s turning off children from different ethnic backgrounds from pursuing a career in science?”

While role models can be helpful, children from all backgrounds must have the opportunity to discover the fun of science, she says. That is the thought behind her first initiative as Astronomer Royal for Scotland: she wants to install a telescope in every outdoor learning centre.

“I challenge you to find any child who doesn’t love space. All kids love space. When you go and talk to them, they love dinosaurs, they love pirates, they love space… I do lots of things with primary schools. They’re just so excited and they just think science is awesome, but then something happens.

“Something happens when they transition from primary school to secondary school. Suddenly science isn’t so interesting anymore and you start hearing things like, ‘science is boring’ or ‘science is too difficult for me’ or just something happens, a change in going from ‘ahh, it’s totally awesome’ to ‘it’s dull’, ‘it’s difficult’.

“And that really upsets me, because I’m still the toddler who loves dinosaurs, pirates and space, you know? I’m still in that, ‘oh my God, it’s awesome’.

“So I’m really interested in what makes that change and looking back at my own childhood, what was it for me that made me not go, science is too difficult? What kept that spark? And for me, I think it was making that actual connection with the universe, to really see it with your own eyes. I think we’re so used to seeing things on TV, on smartphone devices, but it really is quite different to look through a telescope with your own eyes and to actually see the rings of Saturn or the moons of Jupiter.”

The Vera Rubin Observatory in Chile © M. Park/Inigo Films/LSST/AURA/NCF

She adds: “I really wanted to give all of our children the opportunity to do that. Part of the problem is that 80 per cent of Scotland’s population live in the central belt, where our light pollution is such that you hardly see any stars. You can see the moon, and it’s definitely worth looking at the moon through binoculars, and you see some stars but you don’t really get the full ‘wow’, the enormity of when you go to these dark sky places…

"We have these locations in Scotland where most of our school kids go. It’s a really important part of their primary education, if they’ve got the chance to do it. So that’s what I want to do, is to get telescopes installed there and just to give everyone, no matter where you are from, the chance to go to these rural places and really connect with our own solar system and beyond, and hopefully that will give kids the spark to carry on.”

Born in Hitchin, an English town about 40 miles north of London, Heymans always had that spark. She remembers a trip to Scotland as a child when she first saw Saturn, though it wouldn’t be until years later that, as a student, she took her first look through a telescope.

She jokes that she was “a bit of an anomaly” because her parents weren’t much interested in science, but it was an “amazing teacher” who really inspired her. Unusually in the UK, Hitchin is one of few places where the state schools are single sex. I ask whether Heymans thinks that played a role, by removing any peer pressure about gender. She points to studies which have shown that in mixed-sex schools there is a tendency for girls not to take on leadership roles in science classes.

“That goes back to this sort of cultural perception of what a scientist is. Maybe they were going into that experience and going ‘science is not for me, I’ll let this boffin boy do it’. And so they didn’t have the opportunity, whereas for me, in a single-sex school, there was none of that gender stereotyping and somebody had to do the leader role and I enjoyed it, and I still enjoy it today.”

And while tackling these barriers to science is a laudable aim on its own, Heymans also believes it is absolutely essential for future discovery.

“There are these really big questions we’re trying to answer in astronomy, like are we alone in the universe? And how did the universe begin? Major, big questions that we’re not going to be able to answer if the only people who are trying to answer them are coming from the same white privileged education system. You need people coming from different backgrounds, different cultures, different education systems to come at these big questions from different angles and then, with all of that intelligence of mind and knowledge, hopefully, we can answer these really big, fundamental questions.”

Give everyone, no matter where you are from, the chance to go to these rural places and really connect with our own solar system and beyond, and hopefully that will give kids the spark to carry on

Heymans’ expertise is in an area of astrophysics called the dark universe. Put simply, dark matter and dark energy make up around 95 per cent of the universe – but we can’t see it. We only know it exists because of its gravitational effects. Dark matter pulls the universe together; dark energy is what is behind its accelerating expansion. Heymans and her team created the first large-scale map of this invisible dark matter in 2012.

While she casually refers to it as “blue skies research,” it is hoped discoveries in this field will help to answer those big questions. But because there is no direct link to industry or economic benefits, it can be difficult to secure funding, especially after Brexit.

“Since the referendum vote, we got five years of people saying, well, actually no, I don’t want to apply to bring in funding to the UK because I’m not sure if I’ll be able to keep it, it might go. We also had a lot of European astronomers just going, I’m going back, I don’t like this uncertainty.

“We’re in a better position now, because that uncertainty has gone, we are still members of the European Research Council. We can still apply for grants so that’s really, really good.”

She’s also welcoming of new Scottish Government funding, which she says is “doing a fantastic job of mitigating that damage that was done during those years of uncertainty and giving a really clear vision that Scotland is still part of Europe.”

Heymans is adamant about the importance of keeping such international links alive. Not only is she a professor at Edinburgh University, but she is also the director of the German Centre for Cosmological Lensing. Meanwhile, her next big tranche of data is set to come out of Chile, when the Vera Rubin Observatory opens.

Slightly delayed by Covid, the domes of this new observatory will open next year for tests, before becoming fully operational in 2024. Heymans explains: “We’re going to be surveying the entire night sky on repeat for 10 years, building up this picture. Snap, snap, snap across the night sky, piling up, getting this massive picture of the sky on repeat, again and again and again. What this is going to do is it’s going to give us the deepest, widest image of the universe that we’ve ever taken… We’re going to look at how the dark matter is evolving and changing with time, which is really exciting to help us understand how the universe began and how it’s going to end.”

They’re big topics. I ask what brings her back down to Earth at the end of the day. “This is the bonus of having three children. They’re so unimpressed by anything I do, they’re just like, ‘mum, I’m hungry’... They’re very grounding.

“But they are also really inspiring because they just ask questions. The classic example is, what is a rainbow? ‘Oh, I can explain a rainbow to you, it’s where the light is coming through and is refracted through the water droplets,’ and we get out prisms.

“I just love the ‘how does the world work?’ questions. Kids always want to know how does it work, so it’s just great having them there, quizzing you all the time about why things are as they are… That’s what it is to be a scientist, to embrace your inner child and never stop asking why.”