Describing herself as a “dentist for stars”, the X-ray astronomer Victoria Grinberg is interested in some of the most violent environments in the universe – the regions around black holes and neutron stars. Having  originally studied physics the Ludwig Maximilians University in Munich, Germany, Grinberg went on to do a PhD in astrophysics in Erlangen and a postdoc at the Massachusetts Institute of Technology in the US. In 2017 she joined the European Space Agency (ESA), working at its European Space Research and Technology Centre (ESTEC) in Noordwijk, Netherlands.

After a brief spell back in Germany at the University of Tübingen, Grinberg returned to ESTEC in 2021, where she now works as ESA’s first “liaison scientist”, based in ESTEC’s science directorate on the Dutch space campus in Noordwijk. The directorate also has staff in Madrid, Spain, and a smaller group of in Baltimore in the US, working on the James Webb Space Telescope (JWST) and the Hubble Space Telescope.

What does your job as liaison scientist involve?

The title “liaison scientist” always confuses people. Obviously, the “scientist” part simply says “I’m doing science”. The “liaison” part means I’m the link between ESA’s science directorate and the scientific community. My job is to show astronomers what ESA can do for them, whether it’s using data produced by our telescopes, using our archives or proposing science missions to ESA.

But I’m also there to channel information in the other direction. What does the community need from ESA? In what format do they need their data? And what kind of future missions do they want? I’m the first person to hold this job – it didn’t exist before I started. But when I saw it advertised, I thought “Wow, this is exactly what I want to be doing.” I love doing science, but I also love to enable other people to do science.

So you still have plenty of time for fundamental research?

Yes, it’s very much part of my job because I need to be connected to the community. If I want to understand what researchers want, I need to be an active scientist myself. Although we don’t have PhD students at ESA because we’re not a university or a PhD-granting institution, I still have one PhD student back at in Tübingen. Otherwise, I mostly collaborate with people outside ESA.

You’re also a spokesperson for the US and EU-based X-Wind collaboration. What are its aims?

X-ray astronomers often look at X-ray binaries, which consist of a black hole or a neutron star that is gravitationally bound to a normal star. Material from that star is accreted onto the black hole or neutron star, producing X-rays. The companion star is quite often a massive star with very strong stellar winds, and X-ray astronomers looking at these winds tend to think: “Oh my god, it’s so complicated: there’s all this additional absorption, it’s super annoying.”

But at the same time, the winds are a really cool way to learn more about the stars if you are interested in stellar physics. I sometimes compare myself to a “dentist for stars”. When a dentist puts an X-ray machine in your mouth and looks at your teeth, that’s kind of what we’re doing with the stellar winds. We use the X-ray source – the black hole or neutron star – to learn more about the structure of the stellar wind.

The X-ray source is essentially a kind of backlight and we need the stellar wind to pass in front of the X-ray source to really study its structure. So the idea behind the X-Wind collaboration is to bring together X-ray astronomers and people working on stellar winds, who are two very distinct scientific communities. It’s not a big collaboration, like LIGO, but just a loose group of people who want to break boundaries between different parts of astrophysics.

What specific research projects have you got on the go?

I’ve been working with one colleague who does simulations of stellar winds, to develop a way to use the variability of the X-rays from a system to learn more about stellar winds. Imagine you have a lamp and lots of insects flying in front of the it, causing the light to flicker. It’s the same here – you have the stellar winds that are all clumpy, flying in front of the X-ray source.

By looking at the flickering, we can learn more about the stellar winds, how they’re structured, and how much mass the bigger star is losing. X-Wind is also thinking about future missions – such as the Japanese Aerospace Exploration Agency’s X-ray Imaging and Spectroscopy Mission (XRISM), which took off recently and will let us do even more exciting science.

You’re also a co-founder of Astronomers for Planet Earth. How did that begin and what are you trying to do?

I’ve always been interested in the environment and one day in 2019 found myself at a conference of the European Astronomical Society (EAS) in Lyon in the middle of a heat wave. It was over 40 °C, there was no air conditioning and everybody was complaining about the heat. It was really frustrating but then we started asking if maybe we were part of a problem, given we’d flown in from all over the world. A group of us got together but then we realized some folks in the US had already started something similar.

So we brought the Americans and the Europeans together to form Astronomers for Planet Earth. We’re trying to bring awareness of sustainability into astronomy, and to use astronomy to tell the world about the climate crisis. We’re a grassroots organization. There’s not one leader standing out in front: we’re a collection of astronomers at different stages of their careers as well as teachers and journalists – basically anybody connected to astronomy professionally.

You recently co-wrote a paper comparing the greenhouse-gas emissions of in-person and virtual conferences. What were the main conclusions?

The idea for the paper (Nature Astronomy 4 823) came to us during that conference in 2019 where we realized that if we wanted to tell people it’s not very sustainable, we needed numbers. So we got information for about one-sixth of the participants, asking them where they came from and how they had travelled there. We estimated that the CO₂ equivalent for this conference was 1850 tonnes of CO₂, which is about the same order of magnitude as the annual emissions from an astronomy research institute.

The virtual event had more than 1000 times less CO₂ than the in-person event. It wasn’t surprising, but it’s good to have hard numbers

Originally, we were only going to present those findings but then COVID happened and the next EAS conference – in 2020 – was fully remote. Online conferences aren’t entirely carbon free. Every laptop connected to the Internet causes some emissions and then you have to take into account the Zoom servers. Overall, we reckoned the virtual event had about 580 kg of emissions, which is more than 1000 times less CO₂ than an in-person event. It wasn’t surprising, but it’s good to have hard numbers.

In the paper, you suggest emissions from international conferences could be cut by running several regional events at the same time. How would that work?

There are some conferences where people just want to tell each other about the science they’ve done over the last couple of years. Remote conferences are fine for that. But for younger folks –PhD students or new postdocs – conferences are also about networking and forming collaborations. For them, it’s really important to meet in person. So I think concurrent regional conferences are a good balance. The idea would be to have have all the talks online so everyone can listen and ask questions. But you’d have an additional in-person component in local hubs, where people can socialize and discuss ideas during breaks.

Of course, some conferences that consist only of discussions don’t work remotely at all, but maybe we can use virtual reality (VR) for them at some point. Some solid-state physicists have already tried VR meetings and summer schools and been happy with the outcome, but astronomers have so far been hesitant to have a go, which we should.

What are most astronomy conferences currently like: is there any progress towards the goals you’ve mentioned?

Right now, a lot of conferences are back to how they were pre-pandemic – they’re mostly in person. There are some hybrid components to them, but we’re still struggling to find a good way to mix real and online. Part of the problem is that hybrid events aren’t cheap. You need recording devices, you need technicians and possibly professional camera people. Lots of conference centres don’t have the right hardware so they slip back to in-person events because it’s easier. As somebody interested in sustainability, I’m not too happy about that.

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You also do a lot of science outreach, bringing astronomy to the wider public. What do you like most about that kind of activity?

My favourite thing is giving public talks in observatories or at events like Astronomy On Tap. It’s amazing to interact with an audience, to see people excited about astronomy and ask questions. I love seeing people’s eyes light up when you show them pictures of the sky and explain that those are X-ray photons that came from a black hole 6000 light-years away. But I also try to reach out to younger audiences. A colleague and I recently went to a summer school for high-school students in Germany where we talked about our research and what it’s like to be a scientist. That’s great as the audience could ask questions, which isn’t possible if they’re just watching a scientist on TV.

What aspects of astronomy do you find the public are most interested in?

People love black holes, exoplanets and everything related to the planets in our solar system. But what I find people are most interested in – even if they didn’t know it beforehand – is how astronomy is actually done. People often don’t realize that most big space telescopes – and many ground-based observatories for that matter – are international projects that can involve thousands of astronomers from all over the world working together. Once you start talking to people about the human side of astronomy, it really touches them.

You also do scientific illustrations: how did that come about?

I loved art as a kid. I was really good at drawing and, in fact, went to art school when I was around 10 or 12. Then I discovered physics so stopped the art, though I always missed it. But when I tried to restart, I found I was terrible at it, which was frustrating. Then I got an iPad and realized I can do digital art on that. Now I mostly do cartoons to poke fun at academia or to communicate my science.

So what’s your take on the future of astronomy? What challenges and opportunities lie in store for astronomers?

One big challenge is the climate crisis. If things get worse, as they probably will, how can we still do astronomy? It’s both about justifying doing astronomy – given the challenges the world is facing – and also about the negative impact some current scientific practices have on the climate itself.  Another challenge is handling the flood of data from space missions and observatories, such as Euclid, the Large Synoptic Survey Telescope and the Square Kilometre Array. In astronomy, we’re moving away from individuals sitting at their laptops looking at single data sets and more towards big collaborations, where we need to use data science and artificial intelligence (AI) to really understand what’s going on. Sure, there’s a danger because AI and a lot of algorithms are sometimes black boxes. So we need to be sure that we really understand the tools that we are using.

When you’re doing science outreach, do you find people support astronomy or are they more concerned about the costs?

It’s hard to tell because people who come to outreach events have an innate interest in astronomy. But if, say, I’m on a train and people see my ESA sticker on my laptop and ask me what I do, they’re pretty supportive. Astronomy is definitely more in people’s minds than other parts of physics because everybody knows what the sky is, they can still see the Milky Way, and they’ve heard about the Hubble Space Telescope, and seen amazing images of space. People perhaps don’t always realize how complex astronomy is. But I do feel they’re aware it’s a fascinating subject and a way to learn about our place in the universe.

• To listen to an extended interview with Victoria Grinberg, listen to the 21 September 2023 edition of the Physics World Weekly podcast.