Pillars of Dust, Water, and Planetesimals

The formation of terrestrial planets takes place in the opaque inner regions of gas- and dust-rich protoplanetary discs. Hidden from view, microscopic dust particles collide and grow increasingly bigger, eventually coming together in large groups to form kilometre-sized, gravitationally bound planetary building blocks. The properties of these asteroid and comet-like bodies (e.g., their water and carbon content) reflect the conditions in the protoplanetary disc gas (i.e., the local temperature, density, and molecular composition), and ultimately shape the properties of the final planets being assembled.

The recently-launched James Webb Space Telescope (JWST) will offer astronomers an unprecedented view of the surface layers of the warm inner regions of protoplanetary discs. In particular, its infrared spectrograph will be able to detect 100s of emission lines of water and other small molecules like carbon-dioxide, hydrogen cyanide, and acetylene. But how are these datasets, which exclusively probe the tenuous and directly irradiated disc surface, be used to constrain the planet formation processes occurring deeper down in the disc?

In this program, we propose to develop novel simulations of 1-dimensional columns of protoplanetary discs, including chemical processing of dust, gas and ice; material exchange between the disc surface and interior; and the continued creation of "planetesimals". Through these simulations we will be able to link reservoirs that are often treated independently, shedding light on how the early stages of planet formation shapes the appearance of protoplanetary discs as observed through e.g., the JWST.