Short Wave Goes To The Circus Julia Ruth has a pretty cool job: it takes a lot of strength, a lot of balance, and a surprising amount of physics.

As a circus artist, Julia has performed her acrobatic Cyr wheel routine around the world. But before she learned her trade and entered the limelight, she was on a very different career path--she was studying physics.

Julia talks with Emily (who also shares a past life in the circus) about her journey from physicist to circus artist, and how she learned her physics-defining acts.

Short Wave Goes To The Circus

  • Download
  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript


You're listening to SHORT WAVE from NPR.

Before I was a science journalist, I was a circus performer.


UNIDENTIFIED PERSON #1: We're going to just give it right up to the Sitka Cirque performers. Give them a loud round of applause.

KWONG: For real. In Alaska, I joined Sitka Cirque around the same time I started working at KCAW, the community radio station. I needed to do something outside of work. So my days were spent making radio, but my nights were spent making arm muscles.


KWONG: My crowning performance was on two aerial silks, which were tied together to form an elaborate aerial cloud, upon which I climbed, flipped and flew back and forth, dressed as a peacock.


KWONG: I spent hours watching peacock videos on YouTube, figuring out how to move two fans patterned like tail feathers, how to head bob and walk at the same time, how to embody both the confident flirt and the anxious chicken that is the peacock.


KWONG: And it worked. Who was that professional peacock interpreter? - someone asked. Add that to your business card. This is the power of circus - moving in ways that just dazzle people. And for that one weekend, it was the closest I'd ever come to flying here on Earth. For Julia Ruth, that feeling happens all the time. She's a physicist turned circus performer.

JULIA RUTH: So much in circus is that sensation of flying. You're airborne - right? - and you're not connected to anything.

KWONG: Her favorite apparatus is the Cyr wheel, a giant metal hoop tall enough to stand in, allowing Julia to spin and create shapes inside, almost like Leonardo da Vinci's Vitruvian Man.


UNIDENTIFIED PERSON #2: This is a 50-pound stainless steel ring with 1,000 LEDs powered by a flux capacitor.

KWONG: Watching a video of her performance - Julia spinning casually upside down in a candy-cane-colored jumpsuit - I have the same reaction I do to all circus. How is that possible? How is the human body able to do this? That moment of disbelief came for Julia in college. She was a physics major at the University of Maryland and, on a lark, signed up for an acrobatics and gymnastics performance troupe.

RUTH: When I started gymnastics, given that I was 18 with no experience, I think it's easy to believe that I was absolutely awful at it. And my coaches could see that I was really struggling.

KWONG: At the time, Julia was working on something called a flyaway, where you swing on a set of uneven bars and at just the right moment, let go, rotate backwards and land upright on your feet, at least theoretically. That's the goal. Easy, right?

RUTH: And I had just envisioned, like, hitting the bar or landing on my head or just all these awful outcomes. And I was just terrified. And my coach was like, look, if you let go of the bar and you tuck your knees, you're going to rotate. It has to happen. It's physics. And I was immediately like, OK, I can do this now because that was when I could trust physics and then trust my body because of the physics. So I was landing them left and right, no problem. No fears anymore.

KWONG: Hurry, hurry, step right up, under the big top of physics - how Julia Ruth pulls off jaw-dropping tricks and found the courage to pursue her circus dream. I'm Emily Kwong, and you're listening to SHORT WAVE, the daily science circus from NPR.


KWONG: Though Julia discovered she loved circus in college, it wasn't part of the plan. Her whole life was headed towards research scientist. She interned at NASA, worked at NOAA, studied the Arctic and Antarctic regions and, by the time she was 22, was enrolled in a geophysics Ph.D. program at University of California, San Diego, which she picked, in part, because of its proximity to the San Diego Circus Center. And there, Julia's passion for circus grew to the point where she was training three hours a day.

RUTH: Which everyone in grad school thought was insane. Whereas to me, I was like, oh, three hours a day? That's nothing. I'm used to training even longer than that.

KWONG: Because that's what it took to be as good as she wanted to be. So she tried to be both - a scientist and a circus artist. She wanted to know what it was like to perform professionally, and other artists she talked to told her she'd have to choose.

RUTH: Every single one of them told me, look, now is the time. You can't wait. You have to jump with two feet in if this is what you want to do. You can't just dip your toes in the water.


KWONG: So Julia decided to leave her Ph.D. program. She says it was the hardest decision she's ever had to make in her life. Both of her parents had Ph.D.s. They were super supportive of her burgeoning physics career.

RUTH: And so when I broke the news to my family - hey, I've got to go do this; this is what I'm passionate about - that was not well-received at first. I think there was this torn feeling with my parents of, like, we love you and we want you to be happy and we want to support you in anything you do. But also, this path you're on is so prestigious. And we really wanted to have our daughter go through this amazing process that we went through, too, to get a Ph.D. and follow academia.


RUTH: And so that was a tough conversation to have, for sure. But it was a tough conversation for me to have with myself.


UNIDENTIFIED PERSON #3: Check it out. Now, I give you our next act. Julia Ruth on the Cyr wheel - boom.

KWONG: Now, Julia didn't leave right away. She completed her master's degree first, and she fully intends to explore jumping back into science when her circus days are over. But for now, she's a full-time performer. She's done shows in New York, D.C., Chicago, Vegas, even Sydney, Australia. And Julia hasn't left the classroom, either. She teaches online physics classes to middle-school students, and she likes to tie basic principles back to circus. Take, for example, that Cyr wheel - the spinning metal one that turns the performer into a Vitruvian Man. It is, in many ways, the perfect vehicle for understanding things like force and momentum. So get your popcorn.


KWONG: Circus class is now in session.

RUTH: Yeah. So I think my favorite physics property, when I think about Cyr wheel, is torque, right? So there's this axis of rotation, and torque is the measure of a force that causes an object to rotate about an axis.

KWONG: The object being Julia, in the Cyr wheel, making it spin.

RUTH: As a Cyr wheel artist, we always build our momentum as we go. And the way that happens is you're transferring your weight from one foot to the other so that the wheel is rocking back and forth as it is spinning.

KWONG: So it's kind of like pumping the pedals on a bicycle.

RUTH: By using our body - pulling, pushing with arms and legs - we're able to increase the momentum.

KWONG: And your arms and legs are what is generating that torque, that force allowing you to rotate on an axis, like a spinning globe. Fail to maintain your torque, though, and something called your angular momentum, the speed at which you move around that axis shrinks, and you face-plant.

RUTH: And the nice thing is is - OK, I'll be honest. I do fall, especially when I'm learning new skills. I think it's very normal. But the ground is really close.

KWONG: This is a safe space. You can admit it.

RUTH: (Laughter) Yeah, the ground is really close, though, so that's really nice.

KWONG: OK, circus lesson No. 2 - the Spanish web. Now, traditionally, this is an act that takes two. So picture a long, vertical rope hanging from the ceiling. One performer, the flyer, will climb the rope, while the other performer will be the web setter. They'll stay on the ground and spin the rope at the bottom. And the shapes they can make together are kind of mesmerizing.


RUTH: So one of the skills that I do in Spanish web is called a front lever.

KWONG: Yeah.

RUTH: And you extend your legs out in front of you so that your body is perfectly horizontal, with your head facing upward.

KWONG: This is the one that looks incredibly gnarly and superhuman. You're just like...

RUTH: Yeah.

KWONG: ...Your body's in a horizontal, which is ridiculous because you're, like, off the ground. How could you hold yourself in a horizontal position using a rope? Like a flag sticking out there.

RUTH: So when someone is spinning me...

KWONG: Yeah.

RUTH: ...At the bottom...


RUTH: ...Because I'm rotating...

KWONG: They're, like, lassoing the rope around.

RUTH: Exactly. So I'm rotating, and it's a centrifugal force - that is that outward force on a mass. I'm the mass, and that centrifugal force is a result of that rotation. So it's pulling me out. And so it's easier for my legs or my feet to really extend outward.

KWONG: But the Spanish web is as much a matter of strength as it is a matter of physics. Once that centrifugal force is generated..

RUTH: Then my strength comes into play to hit that nice horizontal position.


KWONG: Class dismissed.


KWONG: Back to Julia.

I'm struck by the fact that in order to pull this off, you had to, well, one, learn to trust the physics of circus, but ultimately trust yourself - like, your own physical body and your own power to make a decision, whether that decision is, like, I am going to get in this wheel or I'm going to join this circus.

RUTH: You're absolutely right. There are a lot of decisions I make, and a lot of them are scary. But the way that we grow as human beings is to step outside of our comfort zone. And for me, making scary decisions, trying things that are new, knowing that they're going to make me happy in the long run, is so worth it.


KWONG: Is it safe to say that, if given the chance, you'd make the same decision - that you would leave your program and do this?

RUTH: Oh, absolutely. The second I made the decision, I knew it was the right decision. I haven't doubted it even once since then. And the nice thing is about making a hard decision like that, is that making difficult decisions gets easier because I won't doubt the decisions I make.

KWONG: It's such a cool lesson that circus can teach. I know that personally, from my own life experiences with it. And I just thank you so, so much for sharing yours with us today.

RUTH: Oh, my pleasure. Yeah. I'm just so grateful that people are interested in my story because I'm really happy with what I've chosen to do with my life. And I just - I want everyone to feel that way about their lives.


KWONG: This circus trip was produced by Margaret Cirino. It was edited by Rebecca Ramirez and Gisele Grayson and fact-checked by Rachel Carlson. The audio engineer was Robert Rodriguez. Gisele Grayson is our senior supervising editor, Beth Donovan is our senior director and Anya Grundmann is our senior vice president of programming. I'm Emily Kwong. Thank you for listening to SHORT WAVE, the daily science podcast from NPR.


Copyright © 2022 NPR. All rights reserved. Visit our website terms of use and permissions pages at for further information.

NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.