Date:
Tue, 23/07/202412:30-13:30
Speaker: Dr. Michael Lozovsky (Astrophysics ResearchCenter, Ha-Universita ha-Ptuha, Ra’anana, Israel)
Title: Formation of Ice-Rich Super-Earths: Building and Loss of the Atmosphere by impacts
Abstract:
We investigate the formation and atmospheric evolution of ice-rich super-Earths, emphasizing the role of core accretion processes. Our study focuses on the effects of accretion rate and composition of planetesimals on the planet's internal structure and thermal evolution. Using numeric simulations, we track the distribution of water and rock as the planetesimals accrete.
Our findings reveal that intense heating can cause surface temperatures to reach the sublimation point of water ice, leading to significant ice loss. This process contributes to the formation of a primordial atmosphere, which is then subjected to further mass loss through planetesimal impacts. The efficiency of this atmospheric erosion is shown to depend on the sizes and velocities of the impacting bodies, as well as the planet's gravitational binding energy.
The retention of water vapor and subsequent formation of an ice layer in colder environments is influenced by the initial ice-to-rock ratio and the Safronov parameter. Our results indicate that the ice-to-rock ratios of super-Earths do not necessarily reflect the original composition of the formation zone, due to the complex interplay between accretion dynamics and impact-driven atmospheric loss.
These insights enhance our understanding of the diverse outcomes of planetary formation and provide valuable implications for the characterization of exoplanetary compositions.
Zoom link:
https://huji.zoom.us/j/82952174171?pwd=pdNYlVm7mCUbLQqYHr9qMccTaUOOLI.1
Meeting ID: 829 5217 4171
Passcode: 954403
Contact: Dima Ofengeim
Title: Formation of Ice-Rich Super-Earths: Building and Loss of the Atmosphere by impacts
Abstract:
We investigate the formation and atmospheric evolution of ice-rich super-Earths, emphasizing the role of core accretion processes. Our study focuses on the effects of accretion rate and composition of planetesimals on the planet's internal structure and thermal evolution. Using numeric simulations, we track the distribution of water and rock as the planetesimals accrete.
Our findings reveal that intense heating can cause surface temperatures to reach the sublimation point of water ice, leading to significant ice loss. This process contributes to the formation of a primordial atmosphere, which is then subjected to further mass loss through planetesimal impacts. The efficiency of this atmospheric erosion is shown to depend on the sizes and velocities of the impacting bodies, as well as the planet's gravitational binding energy.
The retention of water vapor and subsequent formation of an ice layer in colder environments is influenced by the initial ice-to-rock ratio and the Safronov parameter. Our results indicate that the ice-to-rock ratios of super-Earths do not necessarily reflect the original composition of the formation zone, due to the complex interplay between accretion dynamics and impact-driven atmospheric loss.
These insights enhance our understanding of the diverse outcomes of planetary formation and provide valuable implications for the characterization of exoplanetary compositions.
Zoom link:
https://huji.zoom.us/j/82952174171?pwd=pdNYlVm7mCUbLQqYHr9qMccTaUOOLI.1
Meeting ID: 829 5217 4171
Passcode: 954403
Contact: Dima Ofengeim