Asteroids from pebbles: Early stages of planet formation
Our understanding of planet formation has changed dramatically with the discoveries of young stellar systems with disks, the large population of extra-solar planets and the behaviour of mixtures of gas and dust present in young proto-planetary disks.
Planet formation begins with the micron-sized dust found in the interstellar medium. In disks it collides to form up to mm-sized grains that feel drag that sends them rapidly into the star which would seemingly end planet formation. The streaming instability is a general behaviour of gas and dust mixtures that rapidly enhances the dust density locally. Dust rich regions soon reach densities where gravity collapses them into loose rubble piles with expected properties similar to those of asteroids and icy outer solar system bodies. These are too large to suffer from drag and gas and can go on to form planets. I present results of simulations of the streaming instability, implications for proto-planetary disks, asteroids and planet formation and targets for future work.
My research group also simulates galaxy formation and related physics including new work on magnetic fields, cosmic rays/diffusion, radiative transfer and processes in the ISM. I will give a brief overview of this work as well including BESPOKE targets for simulations such as PHANGS nearby disk galaxies and cosmological dwarf galaxies.
Dr. James Wadsley is a Professor of Computational Astrophysics and SHARCNET chair in the Department of Physics and Astronomy at McMaster university. He is affiliated with the Origins institute and the school of Computational Sciences and Engineering at McMaster. He has been involved with Canadian national computing infrastructure via Compute Canada (Digital Research Alliance of Canada), SHARCNET and CASCA. He is the lead author of the super computer astrophysical simulation code GASOLINE and his research interests include astrophysics, N-body simulations, parallel computing, fluid dynamics and radiative transfer. His astronomy applications focus on planet, star and galaxy formation simulations. In particular, he studies the formation of asteroids and gas giant planets, the formation of stars and star clusters in galaxies and the cosmological formation and evolution of galaxies in the universe.