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Astrophysicist and newly named MacArthur genius Sara Seager talks about her hunt for exotic new worlds, and draws links between parenting and science

You have been studying exoplanets 鈥� planets outside the solar system that orbit Sun-like stars 鈥� almost since they were first discovered. How did you get into it?
I was wrapping up a project on cosmology and looking for a new project when exoplanets were discovered. My adviser, , thought they were interesting, so I started working on hot Jupiter atmospheres in 1996. I was one of the first people to work on exoplanet atmospheres, and was able to lay the foundations for that subfield.

Why focus on atmospheres?
It was a natural extension of my cosmology work, which explored . Studying photons at different wavelengths is how we know anything about space. So it鈥檚 a natural question to ask about exoplanets 鈥� although a hard one.

Did you know it would get so big?
Not at all. I was just doing what seemed interesting at the time. I call it the random walk strategic path.

What have been the highlights in the field since you began exoplanet research?
Since I started, detection techniques have flourished 鈥� and they鈥檝e succeeded wildly. Now we鈥檙e in the discovery phase, finding exotic worlds. We鈥檙e being surprised over and over again. We鈥檇 get jaded, thinking we鈥檇 seen it all, and then we鈥檇 see something new: circumbinary planets, which orbit two stars instead of one, for example, or compact multi-planet systems. There are so many examples.

What鈥檚 your favourite planet?
It is always the next, most interesting one to be discovered. That鈥檚 my favourite thing about exoplanets, there鈥檚 always something else about to happen.

What鈥檚 next in the hunt for exoplanets?
I personally have a pretty single-minded focus: finding exoplanets where we can use telescopes to analyse their atmospheres and see if they鈥檙e inhabited. There are some proposed telescopes that would help with that, like The Transiting Exoplanet Survey Satellite (TESS) or the Starshade mission concept. But the more immediate future is . They鈥檙e not going to find Earth-like planets, but they may find a whole population of planets we didn鈥檛 know were out there.

You鈥檙e also known for building tiny satellite telescopes called CubeSats. How did you get into that?
I got started doing CubeSats when the mission, which was supposed to directly image Earth-like planets, lost funding in 2005. I was like, well, what can I personally do to keep things moving forward?

The question is, if there is a transiting 鈥淓arth鈥� around a nearby star, how would we find it? The Kepler space telescope was being made ready to go. When I learned about CubeSats, I thought we could make a small telescope and find an Earth.

Admittedly I didn鈥檛 really know what I was doing then. But the thing I love about MIT is that nobody says 鈥渘o鈥�. No matter how hard it is, if you believe in it, someone else will. So we engaged a team of undergraduate students to build , a prototype nanosatellite that could monitor a Sun-like star for two years. The project became really complicated and expensive, like a microcosm of any other space mission. We still haven鈥檛 launched it yet. So we started doing more simple ones 鈥� that鈥檚 how I got into CubeSats.

You鈥檙e known among colleagues for a 鈥榣et鈥檚 do it ourselves鈥� approach. What drives it?
I think it鈥檚 just a personality thing. I don鈥檛 really trust using other people鈥檚 models. You can鈥檛 get inside their heads. We like to do things ourselves and understand them, then you can act rapidly when there鈥檚 a new problem. You know exactly what your model can do.

You were just awarded a of $650,000. How will you use the prize money?
I鈥檓 going to be using it on the home front. I鈥檓 a single, widowed mother. I need to free my brain so I can think creatively. To think creatively is a huge privilege. My husband was very supportive. It鈥檚 overwhelming, running a household by yourself, and also having time with your kids and to do your job right. My kids are 8 and 10 now, so this is perfect timing. This will get me through the next decade.

Is it hard to integrate your roles as a single parent and a rock star astronomer?
It鈥檚 all sort of related. I try to be a creative mom, to think about problems logically, to solve problems the way I would solve them at work: what is the real problem I have to solve, not just what does it look like? And I try to have fun with the kids.