Speaker
Description
Europa, harboring a vast global ocean beneath its icy crust, is considered one of the most promising targets in the solar system for astrobiological exploration and habitability assessment. Understanding its surface chemical evolution and mass loss is crucial for deciphering the composition of the hidden ocean.
Europa is located within the magnetosphere of Jupiter. The electrons and heavy ions such as H$^+$, S$^+$ and O$^+$ in the magnetosphere continuously bombard Europa's icy surface, dissociating water molecules — a process known as sputtering. During this process, incident particles transfer energy to the surface ice matrix, breaking chemical bonds and ejecting volatile species such as H$_2$ and O$_2$ to generate a tenuous atmosphere. Because of the mass disparity, the heavier O$_2$ molecules generally acquire lower initial velocities and remain gravitationally bound near the surface, whereas the much lighter H$_2$ molecules can more readily exceed Europa's escape velocity ($\sim 2.03$ km/s).
In this study, we focus on molecular hydrogen (H$_2$), a highly volatile product whose escape mechanisms are crucial for understanding the moon’s surface chemistry and overall mass loss rate. We use a three-dimensional Monte Carlo trajectory model based on the Restricted Three-Body Problem (R3BP), utilizing the fourth-order Runge-Kutta (RK4) method to track the trajectories of H$_2$ particles under the combined gravitational influences of Jupiter and Europa.
| Participate the oral/poster presentation award competition | Yes |
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