University of Waterloo astronomer Brian McNamara discusses galaxy formation and supermassive black holes, his academic leadership roles, and his life outside of science.
A career in science wasn’t preordained for Brian McNamara. He comes from a family of non-scientists. His dad was an insurance agent. His mom was a voracious reader who stayed home to raise the kids. McNamara’s son, a programmer, is “the closest it comes” to a fellow scientist in the family.
But a chance encounter with a telescope set him on a path to a career spanning five decades at the cutting edge of astronomy, studying galaxy formation and supermassive black holes through work with the Chandra X-Ray Observatory, Atacama Large Millimeter/submillimeter Array (ALMA), James Webb Space Telescope (JWST), X-Ray Imaging and Spectroscopy Mission (XRISM), and more.
A member of the American Astronomical Society since 1989, he was a postdoctoral fellow at the Kapteyn Laboratory in Groningen, the Netherlands; scientific staff at the Harvard-Smithsonian Center for Astrophysics; and a faculty member at Ohio University, before settling at the University of Waterloo in 2006, where he just concluded two terms as Chair of the Department of Physics and Astronomy. He spoke to FirstPrinciples about a career spent perpetually focused on what’s next, his latest work with XRISM (including a recent paper in Nature), and his advice for the next generation of scientists.
The interview has been condensed and edited for clarity.
FirstPrinciples: What inspired you to pursue a career in astrophysics? When did you know this was the right direction for you?
Brian McNamara: What inspired me was the space program in the 1960s. My mother only let me stay home to watch rockets launch. And back then, it was a big thing. I can remember some of the late Geminis and all the Apollos. I also loved to make models and launch rockets.
And then there was also a telescope that my mother had given my dad as a present at one point. It was just sitting in the house. One day, I took it out and just looked at some stars with it. And when I saw Saturn, that was it. I really wanted to do astronomy from that point on. And it’s worked out. It’s been a great path for me.
FP: What fundamental questions are you ultimately hoping to answer?
BM: How galaxies and supermassive black holes formed and co-evolved. A supermassive black hole is this enormous thing at the center of a galaxy, but it’s tiny compared to the size of a galaxy. It’s about the ratio of a grape to the size of the Earth. Yet it is the thermodynamic emperor of the entire system; it determines how a galaxy forms and evolves and there is such an enormous mismatch between the size of these things and the control they exert.
At first, I was just interested in galaxies because they’re beautiful and cool. When I started graduate school, I had no idea what I wanted to do. I got interested in star formation and galaxies and then kind of fell into this with some discoveries we made early in the Chandra days. We were looking at the centers of galaxy clusters, which are radiating energy at a high rate yet remaining hot. We discovered about 25 years ago that it’s the black holes at the center of the galaxies that are keeping them hot.
The question is: How does it do that? In fact, I’m working on that problem right now. With new data from XRISM, our main ideas for how the black hole transfers its energy into heat over a vastly larger volume seem to be crumbling around us. It’s very exciting. I like being in the wilderness where there are discoveries to be made. It’s nice to say, “Yeah, what I’ve been saying for 25 years is right.” But it’s even more fun to say, “We need a rethink on this.” That’s when you’re learning stuff.
FP: What are you hoping to discover from your work with XRISM?
BM: XRISM is a powerful X-ray telescope in Earth orbit. You have to leave Earth’s atmosphere to observe X-rays. And you see X-rays in very hot, energetic environments, like the surroundings of a supermassive black hole.
XRISM has a powerful spectrometer on it, called a calorimeter. It can measure the energy of an X-ray to very high precision by measuring a slight temperature increase in the detector every time an X-ray hits. It gives us superb spectral resolution. We can resolve the emission lines from individual species of elements in the periodic table. We get not only the abundance of the elements, which allows us to study the history of star formation in galaxy clusters, but it also allows us to measure the dynamics of the gas being churned up by the supermassive black hole jets—radio jets that have been emitted from the supermassive black hole.
We want to know what their speeds are and how much turbulence they’re creating. But we’re finding that the gas is remarkably quiescent. Even though it’s being whacked with this enormous amount of energy, it’s not being churned up at the level that we expected. I think we have a really cool discovery here. That’s what I’m working on right now with my students and postdoc. I like to disprove things.
FP: In addition to XRISM, you’re doing some work with JWST. With the abundance of available data right now, do you find it difficult to know where to focus?
BM: I’ve been fortunate in the sense that I’ve sort of made my career by being on the front end of lots of new instruments. I was part of the Chandra X-ray Observatory team, where I had an opportunity to help make important discoveries that shaped my career. When ALMA was developed, six months before the proposal deadline, my team just shifted gears and said, “We know what problem we want to solve. We’re going to work our tails off to be successful.”
It’s the same with XRISM. It’s when you can get in early that you can really make a splash and have some exciting results. I’m not the kind of person that likes to grind away on the same thing, forever using the same instruments.
FP: You’ve served in various leadership roles in your career. Have they impacted how you do your research?
BM: It makes you a hell of a lot more efficient. These roles need to be filled and they need to be filled by senior people. It’s just part of the process of giving back. I came up through the ranks and somebody was always writing grants and paying my salary. There were chairs of departments that I was involved in that had to do all that work. And then at some point, it catches up to you. If you’ve been the beneficiary of an ecosystem that permits you to do what you like, to raise money, to travel and give talks about your work, and so on, you have to give back and make sure you’re paying it forward to the next generation.
I very much enjoy the leadership roles, but it’s a different kind of pleasure and a different kind of thrill. There’s a satisfaction you get if you’ve done something in a leadership role, but there’s a real thrill that you get when you make a new discovery scientifically. It just hits a different part of the brain.
FP: Speaking of the next generation, what advice would you give to aspiring scientists?
BM: Follow your passions and do what you enjoy. You’re going to be a working stiff for most of your life. This is your opportunity to focus on something you love. If you get a physics degree, you can do whatever you like with that degree, but you don’t want to look back with regret.
But don’t do it lightly. Hard work is the key. It really comes down to drive and passion. It takes years and years of grinding, and I say that lovingly. I enjoyed all of that. It’s not a 9-to-5 job. It has to just envelop you. Maybe that’s a little extreme. But most of the successful people I know are like that.
FP: If you do have time outside of work, what do you do for fun?
BM: I have kids who are still living at home, so I’m looking after them and I like to cook. I’m also an amateur musician, a drummer. I’ve been playing with the same guys for about 10 years. We play old Canadian bands like The Guess Who and Sloan. We play Police tunes and we have a very large catalog of songs. We play once a week or once every two weeks, but it is definitely a real passion for me.
