Byrne's research focuses on comparative planetary geology—comparing and contrasting the surfaces and interiors of planetary bodies, including Earth, to understand geological phenomena at the systems level. Byrne’s research projects span the solar system from Mercury to Pluto and, increasingly, to the study of extrasolar planets. He uses remotely sensed data, numerical and physical models, and fieldwork in analog settings on Earth to understand why planets look the way they do.
Byrne received his BA in geology, and PhD in planetary geology, from Trinity College Dublin, Ireland. He was a MESSENGER postdoctoral fellow at the Earth and Planets Laboratory of the Carnegie Institution for Science in Washington, DC, and an LPI postdoctoral fellow at the Lunar and Planetary Institute in Houston, Texas. Prior to joining Washington University, he was an assistant and then associate professor at North Carolina State University.