Speaker
Description
The size distribution of early solar system planetesimals remains poorly understood. Accurate knowledge of this size distribution is crucial for developing more sophisticated solar system formation models. Asteroids are fragments of primordial planetesimals that broke off during collisional events, forming asteroid families, or are surviving planetesimals themselves. By identifying and accounting for all asteroid families, we can begin to assess the surviving planetesimal population.
The current asteroid family catalogs are created using hierarchical clustering method (HCM). However, HCM is known to be ineffective for very old and dispersed asteroid families. In this study, we try to detect another signature of asteroid families, namely the Yarkovsky V-shape, to search for ancient asteroid families.
We focus on the pristine zone of the main asteroid belt (2.82-2.96 au) as this zone is thought to preserve the original planetesimal population better and the existing asteroid families in this region are well identified. We also account for the halos of known families using V-shape constrained HCM to obtain a cleaner background. When looking for V-shapes among the dark bodies (albedo < 0.12), we identified a possible V-shape signature for an asteroid family that could have formed ~4Gy ago. This is possibly the third such ancient asteroid family to be discovered in the main asteroid belt.
