Short Wave - How Clarice Phelps Put Her Mark On The Periodic Table

Episode Date: July 18, 2022

As a kid, Clarice Phelps dreamed of being an astronaut, or maybe an explorer like the characters on Star Trek. And while her path to a career in science was different than what she expected, it led her to being a part of something big: the discovery of a new element on the periodic table. Clarice talks to host Aaron Scott about her role in creating Tennessine, one of the heaviest elements known to humankind.Do you have a great science discovery story? Tell us about it at [e-mail] pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Today on Shortwave, we are setting you a place at our very favorite table, the periodic table, because it's not just for chemists. Everything in the world is made up of the things that are on the periodic table. That's Clarice Phelps, a nuclear chemist at Oak Ridge National Laboratory in Tennessee. What I specialize in are the bottom two rows that nobody else really pays attention to. and those are special to us because they're really heavy elements. Think uranium and plutonium, but also things like curium, Mainsteinium, and Californium.

These heavy elements, the ones with lots of protons and neutrons, they can give us insights into the beginning of our universe, among many other things. They are radioactive, and they decay into other elements that we are able to use for industry, for medical uses, for the military, and for discovering what happened when the Big Bang happened and things that happened in the stars. But many of these elements don't exist naturally.

They've been created by scientists. The process can take years and span the globe. And who knows how many elements we can create. Each one is a new experiment, a new discovery. And Clarice was involved in one of the most recent. I was a part of a team at Oak Ridge National Lab to discover super, superiors. heavy element labeled 117. Today on the show, Clarice tells us how her path went from working on a nuclear aircraft carrier to being part of something big she never expected, helping to discover

a new element on the periodic table, tennis scene. I'm Aaron Scott and you're listening to Shortwave, the Daily Science podcast from NPR. As a kid, Clarice Phelps loved science. She thought she might be an astronaut or an inventor or a character on Star Trek. But her path to a career in science wasn't so straightforward. So, Clarice, before we really dive into some chemistry, I'd love to talk a little bit about your path to working as a scientist, because as I understand it, it's not really the path you envisioned when you got your first microscope as a kid. No, it wasn't. So I had this vision in my head that I guess most people have this path in their head. They're supposed to finish high school, go to college, go to graduate school and get a job, right? That didn't happen for me. So after college,

I couldn't find a job because I did not apply myself. And I will definitely admit that I had a lot of fun in college. And so because of that, I didn't really graduate with a mind-blowing GPA. right? And so I joined the military and I was able to be a part of the naval nuclear power program. I did graduate in the top 10% of my class from Naval Nuclear Power School, which is a very, very challenging course of study. And so after that, I went on two deployments with the Navy and I served on an aircraft carrier. And so I was on the USS Ronald Reagan. We operated two nuclear reactors on board an aircraft carrier. And so, So if you are on a moving, floating nuclear reactor, you really have to know what you're doing.

Uh-huh. I hope so. And then from there, you get a job at Oak Ridge National Laboratory in Tennessee as a technician. Can you tell us a little bit about how the search for Element 117 began and why folks thought it was out there in the first place? So, you know, physicists and astrophysicists and all the isisists. In order to understand the origins of the universe, we have to understand what kind of things existed back then. And these things obviously aren't here now because they've decayed away, they've long been gone. And so the whole purpose is to try to recreate the things that might have existed then.

And so people think that in the early days of the universe, there may have been more heavy elements that quickly decayed into lighter elements. Exactly. Yeah, exactly. So there have been a lot more elements in the universe at that particular instant in time than what exists now. And so scientists want to see what kind of interactions these elements had with each other and what kind of things could have possibly existed. And so that's where the whole drive is, is to understand the beginnings of our universe because everyone wants to know where they came from. Scientists have been creating new elements for a while, working from a seemingly simple idea.

If you slam two elements together with enough force, they could combine. And if those two elements have atomic numbers that add up to, say, 117, voila, a new element is made. So calcium has 20 protons, and berklyum has 97, you add 97 and 20 together, you get 117. And for lack of a better turn, you're just smashing them together. Of course, it's not a simple process at all. Those ingredients can be extremely hard to prepare and isolate. Clarice's role in the project was to extract pure berkeleyum, the atom with 97 protons, from a mix of material that had been bombarded with neutrons,

which, it turns out, left it very hot and very radioactive. You have to cool off radiologically as well as thermally. So you have to handle it remotely. We used remote manipulator equipment. they're kind of like robotic arms to handle the material. So you have all these different isotopes in your material, but you only want the berklium. And so you have to physically and chemically separate them from each other.

It's a painstaking process that can take months. Then they sent the berkeleym to a lab in Russia that had this special equipment to blast it with calcium. Obviously, you can't just like pick up some tweezers and force them together. So the burglum that we purified, what they did is that they created a very thin film, and that film is put on a wheel, which is spun around. And then they shoot this beam.

It could be a calcium beam, a titanium beam, or whatever kind of beam that you can, you know, shoot nuclei at. They shoot this beam at this spinning wheel. On the other side, they have detectors that can detect what kind of decays are happening within that. So you're smashing them together, hoping that they stick.

together long enough to create an atom of an element. They were only able to identify six atoms. Can you imagine that? Six atoms after irradiating this Berklium target with a calcium beam for a year, almost a year. Wow, just six atoms after a year. That is amazing. And so you sent this Spirclium off. It gets blasted by calcium, creates just six atoms of Element 117, which gets named Tennessean. Yeah. So, Clarice, I have to ask, I mean, this is a lot of people working around the world on this project. Is there going to be a use for Tennessean, or why go to such lengths? Currently, no, there is not, like, you can't really physically do anything with it because it exists for fractions of a second. And so because of that, most of the work that would be done

with Tennessee is going to be in modeling and simulation and theoretical. Knowing that it exists and knowing how it decays, it kind of gives rise as to what properties it could have and may not have the same properties as the other elements in that same group. Some people theorize that some of these super heavily elements might give way to new ways of making reactor fuel. Okay, Clarice. So Tenesim was officially recognized in 2016. But I read it wasn't until a couple years later

that the science journalist Kit Chapman realized you were the first black woman involved in the discovery of a new element. Can you remember where you were when you heard that and what that felt like? Yes, I remember this very clearly. I was in church and I got a text message from my friend. And she said, are you okay? And I was like, well, yeah, I'm fine. And she was like, well, girl, you are trending on Twitter. And I was like, what? Look, I didn't have Twitter. I didn't have Twitter. I didn't tweet. So she sent me a link. And there was a lady by the name of Jess Wade who was trying to add more women to Wikipedia. She had heard about my involvement with Tennessee. And she said, I'm looking to reach out to this. lady, I think she might be the first black woman involved with element discovery. And then Kit Chapman replied, she is. And I didn't know who either one of them were. And I just, I kind of didn't

believe it because, you know, at that point, I was like, surely there's, it had to have been somebody. And it kind of, you know, blew up from there. But I was just doing my job. You know, I was just, that was my job at the time. And I wasn't thinking about I'm about to go be the first person to do X, Y, and Z. And so it is an honor to be able to say that and to leave that legacy on history and for my children. But it definitely wasn't planned or expected. I mean, that is just so lovely. And I have to ask then, I mean, what is it like now when you look at a periodic table and you see Tennessee on it? It feels surreal. It felt why. an incredible accomplishment that I could look at a periodic table and say, I had a part in putting that there.

It might have been a small part, but I had my hands on it. Like I had my actual gloved hands. I had my gloved hands on it. I never thought that anything like that would happen to me. and I try to make sure that I now have a platform to encourage and inspire other little girls to reach for the stars and to find out what happens in the universe even if their part is very small, they can still feel the astronomical weight of being a part of something like that. Clarice, it has been such a joy talking the heaviest elements with you and the origins of the universe. And, oh, I love it all. Thank you so much for your time.

Thank you so much for your time as well. I appreciate it. It was fun talking with you guys. This episode was produced by Burley McCoy, edited by Gabriel Spitzer, and fact-checked by Rachel Carlson. The audio engineer was Josh Newell. Giselle Grayson is our senior supervising editor. Beth Donovan is our senior director. Anya Grunman is our senior vice president of programming.

Thanks for listening to Shortwave from NPR. Do you have a favorite thing about the periodic table? I can spell my name with the elements. So you have chlorine, which is C-L-R-Gon, A-R, and then iodine is I, and then C-E-E-E-I-N-S-E. So I can spell my name with elements. Yes, yes, I love that.