Planetary and exoplanetary Astronomy Lunch Seminar (PALS) for 2023-02-27

Series: Planetary and exoplanetary Astronomy Lunch Seminar (PALS)
Date: Monday 27-February-2023
Time: 11:15-12:15
Location: ATL 1250
Speaker: Yun Zhang
Title: Inferring the impact activation process of main-belt comets from their near-perihelion activity pattern

Abstract: Small bodies that contain volatile components hold valuable information about the evolution of the solar system and the origins of life on Earth, as well as be-ing of interest for resource exploration. In recent decades, dust emission driven by sublimation has been detected on several asteroids located in the main belt, known as main-belt comets (MBCs), which suggests the presence of buried ices in these bodies. Previous theoretical and numerical studies have predicted that main-belt objects may be able to retain subsurface water ice throughout their lifetime. These objects can exhibit comet-like activity when impacted by a small projectile that exposes the subsurface volatile ices of a local surface area. All of the MBCs discovered to date only show detectable activities near perihelion. Since the impact location and summer solstice are expected to be distributed randomly, the strongest activity of an impact-exposed area might not necessarily occur near perihelion. In this talk, I will discuss the observational features of MBCs, and present our investigation to explain this discrepancy and shed light on the detailed impact activation process.

For further information contact PALS coordinators Quanzhi Ye at and Tad Komacek at


Special accommodations for individuals with disabilities can be made by calling (301) 405-3001. It would be appreciated if we are notified at least one week in advance.


Directions and information about parking can be found here.

This page was automatically generated on: 20-Feb-2023.