Periodic Reporting for period 1 - EXODOSS (EXOplanet Diversity and the Origin of the Solar System)
Reporting period: 2022-09-01 to 2025-02-28
Fortunately, advances in our observational capabilities, such as those expected from the recently-launched James Webb Space Telescope and the upcoming PLATO mission, will both improve the detection and characterization of Earth-like planets. Also, ground-based observatories, like ALMA, will further probe the discs of gas and dust around young stars in which planets form.
Making use of this anticipated observational progress, this erc grant will fund a team consisting of PhD and postdoc researchers, including myself, for 5 years, with the ambition to do breakthrough theoretical work towards understanding the origin of Earth-like planets. This effort will largely rely on numerical simulations with the aim to link the physical processes in planet-forming discs to those that lead to completed planetary systems.
This research project is important because it aims to address a fundamental question: which conditions are needed to form Earth-like planets? In a larger perspective it will help with shedding light on the delivery -from disc to planet- of key elements, like water, needed for the development of life as we know it.
A first objective is to better comprehend how discs of gas and dust accumulate around newly formed stars and evolve with time. We use state-of-the-art hydrodynamical simulations to model how filaments of gas stream towards to star and build up discs, while they at the same time expel material through jets and winds. Such simulations are the basis for disc model prescriptions used in so-called disc population synthesis. There, we aim to explore the long term evolution of discs in the widely varying conditions in star-forming regions.
A second objective is to study the formation and evolution of planetary systems. Disc synthesis models are the basis to understand the wide diversity in discs that is reflected in the large diversity in observed exoplanet systems. Using a numerical approach, we focus on how newly-formed planetary cores sweep up pebbles. These mm to cm sized particles are the building blocks of planet formation and are observed to be omnipresent in young discs. We furthermore use N-body simulations to model the joined and concurrent formation of multiple planets, allowing the exploration of the linked formation of wide-orbit giant planets and closer-in planets in the Earth to super-Earth regime.
A third objective is to explore, in detail, how exactly pebbles are accreted onto planets embedded in the disc. Planets that are approximately more massive than Mars have semi-bound gaseous envelopes. Using hydrodynamical simulations, we model the dynamical nature of these envelopes and their impact on infalling pebbles that can sublimate volatile species, like water. Understanding this process is therefore key in order to both understand how planets like Earth, as well as more massive planets, evolve in both mass and composition.
Specifically, in the context of the formation of Earth-like planets, understanding their formation and initial composition sets the stage for the early geology and atmosphere of the planet. Looking further ahead, these are the key elements needed to establish the conditions required for the emergence of life, on Earth and possibly elsewhere.