The small worlds orbiting between and beyond the giant planets provide insights into the early history of the Solar System. As a planetary astronomer, I am interested in understanding how they formed, evolved and reached their present orbits. I use wide-field imaging surveys to discover minor planets, and large telescopes to understand their surfaces.

It's been a long road to discovering 840 minor planets beyond Neptune: here's what we found! This article appeared in the March Equinox 2018 issue of The Planetary Society's member magazine, The Planetary Report. Posted with permission.

On its brief passage by Earth, we found the colours of the first interstellar object, 1I/ʻOumuamua, are like those seen in our outer Solar System!

Is there a distant giant planet in our Solar System, yet unseen? Here's what new OSSOS discoveries can say; its signature on distant TNOs is distinctive but very hard to spot in past surveys. The 20,000 year-long orbits of little worlds like 2013 SY99 may instead be from diffusion, as I discuss here.