Planets form in cold discs of dust and gas around young stars like the sun. We know, however, that only a small fraction of the material in these protoplanetary discs ends up in planets; most of the disc is either accreted on to the star or blown away in winds or jets. My PhD and subsequent research investigated these processes in detail, and a comprehensive review of disc evolution and dispersal can be found in our review chapter in Protostars & Planets VI. More recently my research focus has shifted to understanding how protoplanetary disc physics shapes the formation of planetary systems. Recent highlights include ALMA observations and numerical simulations of gaps and rings in planet-forming discs (led by postdoc Giovanni Dipierro, shown on the upper right); breaking mean-motion resonances in multi-planet systems (with former PhD student Tom Hands); and investigating disc warps caused by misaligned planets (led by postdoc Bec Nealon; lower right).
From 2016-21 I am the Principal Investigator (PI) of Building planetary systems: linking architectures with formation (BuildingPlanS), a €1.95M project funded by the European Research Council (ERC). Understanding the extraordinary diversity of the "exoplanet zoo" has become one of the biggest challenges in modern astrophysics. The last decade has seen an explosion in our knowledge of planetary systems, but this dramatic increase in our knowledge has not been accompanied by a corresponding increase in our understanding: despite having discovered thousands of exoplanet systems, we still don't know how planets form, where planets form, or when planets form. BuildingPlanS aims to change this, by linking the observed architectures of exoplanet systems with their formation in protoplanetary discs. We are building detailed computational models to understand the processes that shape the formation and evolution of planetary systems, and testing this understanding against both new observations of planet-forming discs (with facilities such as ALMA and the VLT), and our ever-growing census of exoplanetary systems.
Click here for an up-to-date list of papers from the BuildingPlanS project.
The photo to the right shows the BuildingPlanS team as of February 2019.
From right to left: Enrico Ragusa (postdoc), Giovanni Dipierro (postdoc), Richard Alexander, Cass Hall (Winton Exoplanet Fellow), Giulia Ballabio (PhD student), Bec Nealon (postdoc).