Researcher Spotlight: Dr. Stephen Portillo
Faculty of Science
For Dr. Stephen Portillo, understanding the origins of our Solar System begins not only with telescopes, but with data.
Dr. Portillo’s research program is in astrostatistics, which is developing advanced statistical and machine learning methods to analyze astronomical data.
By applying the right data analysis techniques, astronomers can make new discoveries using existing datasets, overcoming one of the field’s growing challenges: the sheer complexity and volume of modern astronomical data.
“As astronomers build better and better telescopes, the complexity and volume of the data is becoming as much of a barrier as the limitations of our telescopes,” he explains.
His work has been applied to detecting stars in crowded globular cluster images, analyzing galactic spectra using machine learning, and searching for faint trans-Neptunian objects in the outer Solar System.
Developing New Methods
Dr. Portillo is currently developing a method to detect binary trans-Neptunian objects — pairs of distant objects orbiting each other beyond Neptune. While a binary system may appear as a single point of light in one image, analyzing multiple images over time can reveal subtle orbital motion between the two components.
Traditionally, astronomers rely on space-based telescopes to conduct these searches because they provide clearer images. However, Dr. Portillo is building his method for use with ground-based telescopes, which are far more common, with tens of thousands of new trans-Neptunian objects expected to be discovered in the coming years.
These distant objects are remnants from the formation of our Solar System. Studying the trans-Neptunian objects provides insight into how the giant planets made their way into their present-day orbits.
“Astronomy research is about pure discovery,” Dr. Portillo says. “People have always looked at the night sky and asked questions like: how did we get here? My present work is aimed at better understanding how the Solar System formed, and by extension, the conditions under which the Earth formed.”
Real-World Research with Undergraduate Students
At CUE, Dr. Portillo integrates research directly into undergraduate learning.
Students participate in summer research projects, developing statistical and programming skills while working with real astronomical data. Those he has mentored have presented their work at conferences and gained exposure to physics and astronomy research taking place across Canada.
Dr. Portillo’s research is supported by a Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant.