Alumnus: Roshan Eapen (PhD'21)

Dr. Roshan Eapen is an assistant professor at the Pennsylvania State University. He is the director of the Computational Astrodynamics Research and Experiments (CARE lab) and the Penn State University Dynamical Observatory (PSUDO). Prior to joining Penn State, he completed his UG in Aerospace Engineering from Karunya university, M.S. from Purdue University and Ph.D. in Aerospace Engineering from Texas A&M University in 2021.

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AEGSA: How would you briefly describe your professional background? Roshan: My professional background has been a journey of accumulating perspectives, with each step adding a new layer to my understanding of astrodynamics. It began during my undergraduate studies at Karunya University, where I first became captivated by the elegant complexity of the three-body problem and its geometric structures. That initial spark led to early work designing transfer trajectories from Earth to Mars and an internship at the Vikram Sarabhai Space Centre, where I explored low-cost, ballistic capture trajectories for lunar and Martian missions. This was the foundational, "what if" stage of my career, driven by pure curiosity about the dynamics governing celestial motion.

My time at Purdue University for my Master's was about building a robust toolkit. I was immersed in the practical and critical domains of space situational awareness, high-fidelity dynamics modeling, and numerical averaging techniques. My Ph.D. at Texas A&M University was where these threads began to weave together into a cohesive fabric. It was an incredibly diverse experience where I developed analytic and numerical techniques for a wide range of applications, from understanding chaos in rigid body dynamics to formulating a new approach to optimal control using Hamilton-Jacobi theory. A pivotal moment was receiving the Heep Graduate Fellowship from the Hagler Institute of Advanced Studies, which allowed me to dive deep into cislunar transport mechanisms—an exploration that has become a cornerstone of my work today. Now, at Penn State, these explorations have culminated in the Computational Astrodynamics Research and Experiments (CARElab), a name I chose specifically to reflect my core philosophy: a constant, dynamic interplay between theory and practice, where each informs and elevates the other.

AEGSA: Reflecting on your time in graduate school, what stands out as your most memorable experience and how has it influenced your career?

Roshan: My most memorable experience was, without a doubt, my Ph.D. preliminary examination. It was an intense multi-part assessment: a take-home exam on estimation and optimal control, a written exam on conceptual astrodynamics, and finally, an oral exam covering a breadth of topics in dynamics and control. During the oral portion, I was asked to derive Kepler’s equation, a task that is considered fairly elementary in our field. I began the derivation, but soon found myself going in circles, trying to force a particular method to fit the answer I already knew was correct. There was a palpable silence in the room as I struggled at the whiteboard, and then a voice from one of my advisory committee members gently broke the tension: "You know," he said with a smile, "Newton had to invent a whole field for obtaining Kepler’s equation the way you are trying to do!"

That moment, with its perfect blend of challenge, humility, and good-natured humor, has remained etched in my memory. It influenced my career by teaching me a profound lesson that goes far beyond any single equation. It taught me to respect the problem. I was so focused on demonstrating my knowledge of a certain technique that I failed to listen to what the problem itself was asking. As the physicist Richard Feynman said, "The first principle is that you must not fool yourself - and you are the easiest person to fool". In that moment, I was fooling myself. The experience instilled in me a deeper intellectual humility and reinforced the importance of returning to first principles. It taught me that the most elegant solution often arises not from forcing a preconceived method, but from achieving a clear and fundamental understanding of the question being asked.

AEGSA: During your time at A&M, what accomplishments are you most proud of in terms of your professional contributions or impact on research (or) teaching?

Roshan: Looking back at my time at Texas A&M, I feel an immense sense of gratitude for the opportunities I was given. The accomplishment I am most proud of is receiving the Heep Graduate Fellowship from the Hagler Institute of Advanced Studies. This fellowship was more than just financial support; it was a transformative opportunity that immersed me in a vibrant intellectual environment. It provided me with the most valuable resource a doctoral student can ask for: the time and freedom to go deep into a challenging subject. It was during this time that I was able to truly dedicate myself to understanding the foundational questions of cislunar transport mechanisms, work that has become a central pillar of my current research program.

Secondly, I am also proud of the image generation and processing pipeline I helped develop as part of a DOD STTR project. The time I spent using a physical telescope to track satellites was invaluable. I believe this hands-on experience is what prepared me to establish the Penn State University Dynamical Observatory (PSUDO) and gave me the confidence to push the state-of-the-art in image-based satellite characterization. Both of these experiences from my time at A&M were direct seeds for major research thrusts I am leading today.

AEGSA: As a student, what was your routine for weekly meetings with advisors? Can you talk about your note taking and reporting, how it helped you write your dissertation?

Roshan: I was fortunate to have advisors who were generous with their time and deeply invested in the intellectual process. During my first few years, we met weekly, sometimes multiple times a week. These meetings were often informal - at the Azimuth Café in the architectural building or Panera - and were less about reporting progress and more about collaborative discovery. They were true working sessions, bouncing ideas off each other and putting pen to paper to derive equations together. As I progressed, my advisor gave me the creative freedom to forge my own path, encouraging me to develop my own ideas and research topics. It’s a mentorship style I strive to emulate with my own students.

To support this process, the most crucial tool I developed was a detailed research journal. This wasn't a polished document; it was a raw, chronological log of my entire intellectual journey. It contained everything: derivations that worked, code that failed, promising ideas, and the inevitable blind alleys. I documented not just the "what" but the "why"— my thought process, my assumptions, and the questions that arose at each step. This practice was absolutely indispensable when it came time to write my dissertation. I wasn't starting from a blank page; I had a detailed record of the entire story of my research. The structure of the dissertation emerged organically from the journal, allowing me to build a coherent narrative explaining not just the final results, but the path taken to get there. The journal was my way of ensuring I truly knew my research in all its messy, authentic detail, rather than just knowing how to summarize it.

AEGSA: How does the research you conducted during your graduate studies align with and contribute to your current work as a faculty member?

Roshan: The alignment between my graduate research and my current work is not just strong; it is foundational and direct. My time as a Ph.D. student was the period of seeding ideas, and my role as a faculty member at Penn State is about cultivating those seeds into a flourishing research program. The intellectual threads I began to pull at Texas A&M have become the primary pillars of my CARElab. I can draw a straight line from specific doctoral projects to major, funded initiatives my students and I are pursuing today.

For example, at TAMU, I developed a relatively new paradigm for solving optimal control problems using Hamilton-Jacobi theory. Today, at Penn State, two of my graduate students are extending this exact theoretical framework to tackle guidance, navigation, and control challenges in cislunar space. Similarly, my Ph.D. work on developing a physically-based ray-tracing pipeline for sensor simulation has evolved into a sophisticated software suite that my students now use. My time spent on imaging satellites/planets using telescope at TAMU has provided the foundational experience for establishing the PSUDO telescope facility. Finally, the deep dive into cislunar transport mechanisms I undertook as a Heep Fellow at TAMU has directly led to my role as a Co-Investigator on the multi-university AFOSR CHANCE project, which is a significant expansion of that foundational work.

AEGSA: Looking back, what motivated you to transition into a faculty position, and how has that decision shaped your career path?

Roshan: My motivation to become a professor stemmed from what I see as a dual calling: The first is an insatiable curiosity - a deep-seated desire to wrestle with the universe's most beautiful and complex dynamical puzzles. The second is the profound satisfaction that comes from sharing that passion and igniting that same spark of curiosity in others. A faculty position is the only career path I know of that doesn't ask you to choose between these two callings; in fact, it insists that you pursue both with equal vigor.

This decision has shaped my career by reinforcing my belief that research and teaching are not separate activities, but two sides of the same coin. I strongly believe that research should integrate with teaching and mentoring. Students learn better when they see how fundamental concepts apply to complex problem solving, and research should begin from first principles. I try to put this philosophy into practice every day. My research on cislunar dynamics provides exciting, real-world examples that I bring into my undergraduate classroom. In turn, the process of breaking down these complex ideas for students often reveals a new perspective or a more fundamental way of understanding my own research. I find it to be profoundly true that to master something, you must teach it.

AEGSA: Can you provide insight into a typical day in your life as a professor, and how you enjoy your free time? Any favorite travel experiences?

Roshan: There is rarely a "typical" day, which is one of the things I love about this job! A day likely involves a blend of teaching, research, and mentoring, and it varies from semester to semester. I meet with my students at least once per week, but I maintain an open-door policy and encourage them to stop by whenever they run into an issue or want to bounce ideas around. I try - and admit that I have not yet mastered it - to dedicate focused time to my own research, whether that's brainstorming with colleagues, writing grant proposals, or fulfilling service duties like reviewing papers and serving on committees. It's a constant balancing act.

My free time is often an extension of these passions. I've always been fascinated by the night sky, and my work setting up the PSUDO telescope in New Mexico has been a wonderful fusion of hobby and profession. As for travel, I cherish the opportunities to attend conferences. They are not just about presenting research; they are about reconnecting with the global scientific community, sharing ideas in hallways between sessions, and feeling part of a collective human endeavor to understand our universe.

AEGSA: In your eyes, previously as a graduate student and currently as a professor, was there any resource missing that you felt could have impacted your student experience?

Roshan: Reflecting on my journey, the "missing" resource I see is not a physical thing, but a structural one: a greater number of formal, interdisciplinary forums or "sandboxes" designed to break down the traditional silos between departments. As a graduate student, I was naturally drawn to the intersections of dynamical systems, control theory, and computational vision, but finding collaborators and mentors in those adjacent fields often relied on serendipity and individual effort. I often wished there were more structured opportunities to engage with students and faculty from applied mathematics or computer science on shared problems.

Now, as a professor, I see the immense power of such collaboration firsthand. My work on the CHANCE project brings together researchers from four different universities, and my collaboration with the Applied Research Lab at Penn State on virtual reality visualization involves crossing college and department lines. These experiences have reinforced my belief that the most innovative solutions often emerge from the cross-pollination of ideas. We often cut nature up into different departments for our convenience, but nature doesn't know it. Creating more spaces where we can ignore those artificial boundaries would be an invaluable resource for the next generation of students.

AEGSA: Can you share your experience with the application process for a faculty position – what are some challenges you faced, and what helped?

Roshan: The faculty application process is a uniquely challenging experience. The primary difficulty, I found, was the mental task of projecting a compelling and distinct vision for a future research program while simultaneously being immersed in the all-consuming effort of finishing a dissertation. It requires you to operate on two different timelines at once: completing the work that defines your past while articulating a credible and exciting story about your future.

What helped me most was focusing on crafting that future narrative. The process of writing my research and teaching statements - was the single most valuable preparation I did. It forced me to step back from the daily details of my thesis and ask the big questions: Why does this work matter? What are the fundamental questions I want to spend the next decade answering? How will I build a lab and mentor students to explore those questions? Having a clear, passionate, and well-rehearsed answer to the "why" behind my work was crucial. Equally important was the support of my network at Texas A&M and outside – advisors and friends. I am incredibly grateful for the mentors and peers who conducted mock interviews with me, provided candid feedback on my application materials, and offered constant encouragement.

AEGSA: From your perspective, does being a postdoc contribute to launching a successful academic career? Should a graduate student consider doing a postdoc first?

Roshan: This is an excellent and important question, and my perspective is that there is no single, correct answer. I believe it's a mistake to view the postdoctoral position as a default or mandatory step. Instead, it should be viewed as a strategic tool that can be deployed for specific purposes. The critical question a graduating student should ask is not "Should I do a postdoc?" but rather, "What specific goal would a postdoc help me achieve that my Ph.D. has not?"

A postdoc can be an invaluable strategic move if you want to acquire a new skill set that complements your own, work with a particular world-leading expert in a new domain, or build a publication record in a new area to broaden your research portfolio. However, it is not always necessary. I was fortunate to come out of my Ph.D. program with a very well-defined research vision that was already gaining traction, which gave me the confidence to move directly into a faculty role. My advice to students is to be introspective. Perform an honest assessment of your own profile and research vision. Is your program ready to stand on its own, or would it be significantly strengthened by another period of focused development under a different mentor? One must think for themselves and not simply follow what is perceived to be the standard path.

AEGSA: What advice would you offer to current graduate students who aspire to pursue a career in academia and a successful graduate experience?

Roshan: If I could offer a few pieces of advice for a successful and, more importantly, a fulfilling graduate experience, they would be these. First, fall in love with a problem, not a specific solution or method. Let your curiosity about a fundamental question be your guide. This is what will sustain you through the inevitable challenges and setbacks. Second, learn to embrace the messy, nonlinear process of discovery. Real research rarely follows the clean, linear narrative you read in published papers. As I learned, keeping a detailed journal of the "blind alleys" and failed attempts is just as important as documenting the successes.

Third, and perhaps most importantly, learn to be comfortable with not knowing. The frontier of knowledge is, by definition, a place of uncertainty. It is far more interesting to live with questions you can't answer than to have answers you can't question. My own humbling prelim exam experience was a powerful lesson in this. Finally, be a generous citizen of your intellectual community. Your success is tied to the success of those around you. Help your peers, ask questions in seminars, and take mentorship seriously. A career in academia is not a solitary pursuit; it is about being part of a great conversation, a continuous chain of discovery passed from one generation to the next.

AEGSA: What keeps you up at night and what gets you out of bed in the morning?

Roshan: Among many, many things, personal and professional responsibilities, what keeps me up at night is a sense of wonder. It’s the excitement of wrestling with a particularly tricky piece of code for a simulation, or the process of sketching out a new mathematical approach on a whiteboard and wondering if it will work. It’s the thought that a new perspective on a problem could reveal something we hadn't seen before. It’s the pleasure of the puzzle, and sometimes that puzzle is so engaging it’s hard to switch off.

What gets me out of bed in the morning is the other half of that equation: the chance to share that pleasure. It’s the opportunity to walk into a classroom and see the spark of understanding in a student's eyes as a difficult concept finally clicks. It is the profound privilege of being a link in an intellectual chain - receiving knowledge and passion from my own mentors and having the daily opportunity to pass it along to the brilliant young minds that will carry it forward. And, not in the least, it is the opportunity to tackle new and important questions – questions that others have not yet asked, or even thought about!