ZTF Faces

Erik Kool

Postdoc at the University of Stockholm, Sweden

Where was your starting point and how did you discover astronomy?

I am from the Netherlands, where I grew up in a town close to Utrecht. My road to becoming an astronomer hasn’t been a particularly straight line. I have worked as a climbing and outdoor instructor, a consultant, and even a brief spell as a professional poker player. There are so many fun things you can do, and I’m glad to have had all those experiences, but also happy I ended up being an astronomer.

How did you discover ZTF?

I followed my bachelor and master studies in Utrecht, where I was one of the last students to graduate before the Astronomy department tragically was shut down. As a last hurrah, the astronomy department spent all its money on a large national conference, with everything paid for. This gave me a very skewed idea of how astronomy conferences are held!

For my PhD I moved to Sydney, Australia, where I got involved in a project looking for supernovae buried deep in the dusty inner confines of galaxies. Finding any supernova was a reason for celebration, I think in total we discovered about half a dozen over the 4 years of my PhD. When I interviewed for my postdoc position at Stockholm University, I was informed that ZTF finds that many on a nightly basis!

What are you playing with in the ZTF playground?

I have to admit, it took some time to get to grips with the flood of transients that come your way as part of ZTF. Eventually I found my niche, of supernovae that interact with hydrogen-poor circumstellar material. My work on a sample of such supernovae allowed me, with the help of colleagues, to recognize that one supernova in my sample was quite unlike the others. This study, of a Type Ia supernova interacting with helium-rich material, is about to be published in Nature, and is definitely a highlight of my career so far.

Where do you want to steer your rocket in the future?

Looking ahead, I am moving to Finland later this year to continue working on supernovae and other transients.

If you were not an astronomer, what would you be?

If I wasn’t an astronomer, I assume one of my other interests would’ve taken precedence. As I said, I have worked as a climbing and outdoor instructor, a consultant, and even a brief spell as a professional poker player.

A book that shook your worldview?

A recent book that impacted me was The Biggest Bluff, by an academic who writes about her attempt to learn poker, having no idea about the game initially. It's not a rags to riches kind of book, or some kind of poker instruction. It's about how one can learn through a game, that normal life is full of chance and randomness, and that accomplishments or failures are only loosely correlated with your effort, skill and capability. You do your best, and then the chips fall where they may. Bad outcomes, also in academia, are not a reflection of your worth. Good outcomes too, for that matter.

If you’ve had a bad day at work, you will….

If I’ve had a bad day at work, I usually just go outside, go mountainbiking/climbing/hiking etc. A recent favorite is to pick up my daughter early from preschool, and go for a run or hike with her in the pram or carrier. It’s quite hard work nowadays as she has grown quite a lot, but she is an excellent coach. Anytime I stop running for a bit, for example when going uphill, she starts yelling “daddy run!”.