For Johnny L. Worthy, III, it all started with a box of Space Shuttle-themed Legos.®

“My parents say that once I got those Legos®, I was off. No looking back…I always wanted to be an astronaut after that,” says the 22-year-old AE doctoral student, a recent recipient of a National Science Foundation graduate research fellowship.

“It got even worse when I visited the Kennedy Space Center a few years later. But, really, those Legos® started me. That’s really how I ended up at Georgia Tech.”

Legos – and a whole lot of work.

Since coming to Georgia Tech in 2009, Worthy has had his natural aptitude for math and science put to the test on several occasions. For the most part, he has triumphed but not always. Freshman year, the only class he didn’t ace was aerospace engineering.

“That class was hard, really hard, but my reaction was ‘I can do better than this.’ I never thought about giving up on aerospace engineering. Never.”

His direction within the field has shifted, however. These days, he’ll tell you that if he doesn’t become an astronaut, he’ll be just as happy to design a better spacecraft. Or a better orbital path for that spacecraft.

“I’ve focused a lot on building a base skill set in orbital mechanics - a gateway to the study of design and trajectory of spacecraft,” he said. “I’m just now beginning to enjoy what I’m doing because I’m able to ask more questions about what I’m observing.”

Under the mentorship of his advisor, Dr. Marcus Holzinger, Worthy’s research in AE’s Space Systems Design Lab (SSDL)  has focused on detecting, tracking and predicting the movement of various objects in space – space situational awareness – using both mathematical simulation and direct observation.

The research team has simulated the orbits of thousands of objects, all in an effort to better predict the environment in which approximately 1100 satellites circle the earth. Worthy has also collected data on objects located through a telescope at different times of day and at different angles.

“When we see them and can identify them, the question, then is: what orbit are they in? Is it the same as the ISS [International Space Station]?”

He is particularly drawn to the predictive qualities of his research.

“The math isn’t straight forward on these simulations – you are dealing with six dimensions – but you begin to see relationships between the velocity of the object and its position, and that can help us in a lot of ways,” he said.

“Knowing exactly where a satellite is and where it will be can help us avoid collisions, which would be chaotic.”

In his application for NSF funding, Worthy explained the theoretical underpinnings of his approach, which will comprise the bulk of his doctoral work. It is at this point that it becomes crystal clear how far he’s come from his Lego® days.

Broadly put, his goal is to “determine the state of a system in an information-deficient environment” – an environment that has unobservable or hidden states, like space.

“There are many examples of undetermined problems in state estimation,” he writes.

“One class of problems in which this method applies is the future position of an object…furthermore, since [the object] could be anything from a threat to a lost child, this research could also enable technologies which improve safety and security in everyday lives.”

Johnny L. Worthy III will be spending his summer at MIT’s Lincoln Labs, where he will contribute to work on space system analysis. Last summer, his work at the same lab focused on missile defense systems.