The Team

Vincent Bian


I am a senior at Poolesville High School, in Poolesville, Maryland.

In preschool, every picture I drew was of the nine planets (yes, Pluto was still a planet back then). Later, this obsession took a backseat to my other interests, but I was always fascinated with space. I still remember the rocket launch I watched at Cape Canaveral, and the livestream of New Horizons as it approached Pluto. Since then, I’ve watched every rocket launch that I could.

Throughout middle and high school, I had math, and then physics, as my “main” subjects. I must have spent hundreds of hours preparing for math competitions. My math skills made learning physics a lot easier, and I spend more hundreds of hours preparing for physics competitions, which gave me a huge head start on astrophysics. Despite this, I might have forgotten about astronomy, if not for a friend of mine, to whom I am deeply grateful. He persuaded me to take USAAAO in junior year, which led to me making the IOAA team, and more importantly, reminded me how awesome space is. I am also grateful for the opportunity to be on the team, which helped me rediscover my love of astronomy.

In the future, I want to work in a STEM field, and solve cool problems with cool people.

April Cheng


I am a junior at Canyon Crest Academy, in San Diego, California. I am 16 years old. I’ve been interested in the cosmos since before I even went to school. Starting from space-related picture books, moving on to kids’ astronomy books, and finally to more advanced texts and documentaries, I was curious about astronomy all throughout my childhood to the present. My middle school’s Science Olympiad program was my first insight on the more astrophysical side of astronomy. My success in Science Olympiad gave me the first motivation to compete in this area, and I first participated in USAAAO in my freshman year, and finally qualified to the international team in my sophomore year. I hope to learn more about astronomy and astrophysics throughout high school. In the future, I want to do research in astronomy or astrophysics, as I wanted to since elementary school. I am immensely thankful to the Science Olympiad program, of which I am currently an organizer and a coach for my school, for sparking my interest into a passion, and also to the USAAAO and IOAA for giving me an opportunity to compete.

Outside of school, I love playing video games, reading, and watching TV shows. I also love ice cream regardless of the season.

Joseph McCarty


 I am a junior at Lubbock High School in Lubbock, Texas. I’ve been interested in astronomy and physics since my first exposure to them in 4th grade, but I didn’t realize how satisfying they could be until my mathematical understanding increased as I went into high school. Over the years since, I have been inspired to learn as much as I can on my own by the depth and significance of the questions answered by astronomy and physics. For that reason, I find cosmology particularly fascinating because it seeks to answer questions about the fundamental nature and history of the universe, but I also enjoy pretty much every other aspect of astronomy. One thing this competition has exposed me to much more is stargazing, and I just recently realized how close I live to incredible dark skies. Stargazing is a hobby I hope to pursue after high school as well. In the future, I hope to keep learning more and eventually have a career in some field of physics. Outside of astronomy, I enjoy doing math, playing cello, hiking, playing soccer, and reading Wikipedia articles with little relevance to anything else.

Sahil Pontula


For as long as I can remember, I have gazed up at the night sky with awe. Over time, as I watched NOVA episodes on astrophysics and read Stephen Hawking’s “A Brief History of Time”, I realized that my love for astrophysics was more than just a phase. This motivated me to participate in the “Reach for the Stars” Science Olympiad event in eighth grade. I found myself reading through research articles, and broadening my perspective on astrophysics. I continue to participate in the “Astronomy” Science Olympiad event in high school and co-captain my school team, no longer daunted by the mathematical and physical complexity of astrophysics and eager to follow the latest research in the field.

Beyond academics, I enjoy playing the piano and playing soccer. Every summer, I look forward to hiking at a national park with my family. This has driven me to direct my volunteer efforts towards environmental advocacy since I have realized that both preserving our natural treasures and clearly observing the night sky depend upon minimal air pollution.

My favorite area in astrophysics is probably the physics of compact objects (such as SNRs). I am intrigued by how much there is to learn from the bizarre states in neutron stars and black holes, and am fascinated by the joining of relativity and quantum mechanics at such high densities.

I am a junior at Enloe High School in Raleigh, NC, and I look forward to attending the 2018 IOAA. I am grateful to the USAAAO coaches for their extraordinary training, which has reaffirmed my passion for astrophysics and has inspired me to continue probing the theoretical and observational advances in astrophysics, a field I hope to contribute to in the future.

David Yue


Since a young age, I’ve always had an interest in the big questions. Where did we come from? What’s outside the universe? Does time only move in one direction? This desire for understanding and unquenchable curiosity brought me to astrophysics, where I realized I could actually find answers to my queries. My original questions have now translated into studying ultra-high-energy cosmic rays, learning about large quasar groups, and conducting recordings of exoplanet transits. I’m incredibly thrilled to be working on studies of the immensely large that encompass our entire existence, such as through understanding cosmological models, all the way to the most infinitesimal, like quarks and leptons. It is through the investigation of all things in our universe, big or small, that we can find new discoveries to answer our constantly evolving questions. I’m excited to continue my astrophysics journey at the IOAA, and even more proud to have this experience to advance my learning. Space may be the final frontier, but our research of the uncharted has just begun.

Andy Zhu

Andy Zhu

I remember in 2nd grade my teacher asked us to write our dream profession on a piece of paper. I, along with most of my peers, wrote down the word astronaut, not knowing what that actually entailed. Back then, I was just interested in the idea of going to space and meeting ET.
However, due to imperfect eyesight, I would never be able to sail off to the moon.
Since I couldn’t blast off to space, I decided to pursue something else. I learned that math and sciences provided the foundations to understand the way our world functions.
When I heard about my middle school’s Math and Science Olympiad programs, I naturally joined both.
I soon fell in love with both as they both taught one common idea: problem-solving.
Through applications of basic principles, complex problems were broken down into bite-sized, manageable pieces. These math and science competitions honed my ability to solve problems.
In 10th grade, I had the opportunity to take an astronomy course at a local college. After the first class, my childhood fascination was immediately reawakened. But this time, I was more interested in the problems solving, technical side than the dream of going to space.
Since then, I’ve furthered my studies by completing An Introduction to Modern Astrophysics by Carroll and Ostlie. Throughout my astronomy journey, I’ve developed an interest in a few particular subjects, namely those that we do not understand. Space contains some of the most extreme phenomena such as colliding black holes and degenerate matter. In order to better study these, I wish to improve telescope capabilities in the IR range.
Outside STEM activities, I enjoy ultimate frisbee, card games, and movies.

Team Leaders

Natasa Dragovic


I am a graduate student in mathematics at the University of Texas at Austin and I am one of the team leaders and coaches of the team USA at IOAA 2018.
I was born and raised in Serbia, and later I came for college to MIT where I studied math.
During middle school and high school, I competed for Serbia at four International Astronomy Olympiads (IAO) and one International Astronomy and Astrophysics Olympiad (IOAA). A big part of success of our team was due to many teachers that helped us prepare. In particular, a retired physics teacher, prof. Ratomirka Miler, gave a lot of her time and was the major driving force. I hope that I can pass on some of the knowledge I gained then to the team.
I think that science olympiads are great for students to learn more advanced curriculum at young age, meet people from all over the world with similar interests and make lasting friendships.
Despite not studying astronomy any more, I enjoy being involved with the competition and helping students prepare. Besides USAAAO, I am also involved in organizing the Directed Reading Program in my department. We pair undergraduate students that are passionate about math related topics with a graduate student in order to read a book during a semester and learn a new topic (

Ioana Zelko

I am a PhD researcher in astrophysics at Harvard University. I am originally from Romania, and I came to the USA in college to pursue a physics degree at MIT. During my time in high school in Romania, I participated in many international science competitions, like IPhO, IOA, IJSO, and most importantly, two editions of the International Olympiad of Astronomy and Astrophysics. The olympiads meant a lot to me, on personal and professional level. They gave me the chance to pursue a rigurous training in science, and to connect with many peers with similar interests. Eventually, they ended up informing my career choice.
I find passion in teaching and learning, and I appreciate the chance of doing both of them at the side of the USA national astronomy and astrophysics olympiad team, as a coach and team leader. Organizing the selection and training the team is a hard but rewarding process.
In my day to day life I spend time working on research, and a couple of other projects. During my time at MIT, my research focused on building a interferometer telescope. You can see a video of the result here Now, during my PhD, I am looking at interstellar dust. Aside from research, together with three friends, I started the project PhysicsDen (, a website that hosts physics problems related to published research, in attempt to bridge the gab between class material and research. Check us out!