April 24, 2023 Nancy Chabot

We are delighted to announce the selections for the 2023 Pellas-Ryder Award. This award is jointly sponsored by the Meteoritical Society and the Planetary Geology Division of the Geological Society of America and honors outstanding first author planetary science papers by students.

Hui Ching Jupiter Cheng, who obtained a Ph.D. in 2023 from the University of Georgia, Athens, GA, USA, is a co-winner of the 2023 Pellas-Ryder Award for the paper entitled “Structural relationships in and around the Rheasilvia basin on Vesta” published in the Journal of Structural Geology in 2022. Jupiter performed a thorough, detailed structural analysis of the basin, and found, contrary to previous interpretations, that the Divalia Fossae cross-cut the basin and are not concentric around the basin center, and therefore formed after it and are not directly related to the impact that formed the basin. This work is likely to inspire follow-up studies, leading to reexamination of the formation of the Rheasilvia basin and improvement of our understanding of Vesta.

C. Adeene Denton, who obtained a Ph.D. in 2022 from Purdue University, West Lafayette, IN, USA, is a co-winner of the 2023 Pellas-Ryder Award for the paper entitled “Tracking the evolution of an ocean within Mimas using the Herschel impact basin”, published in Geophysical Research Letters in 2022. Adeene modeled impacts into an icy moon with an ice shell and underlying ocean of varying thicknesses to understand the formation of the Herschel basin on the Saturnian moon Mimas. The results place constraints on the thickness of the ice shell at the time of impact and have implications for the evolution of Mimas’ shell and its ocean post-impact, and for our understanding of icy moons in general.

Congratulations to the 2023 co-winners for this highly deserved honor and for leading these impressive studies! We also thank everyone who submitted nomination packages and the Pellas-Ryder Award Committee for their work to make this award possible.

Based on reports submitted by: Steve Simon, 2023 Pellas-Ryder Award Committee Chair

Published in MAPS in June 2023: https://doi.org/10.1111/maps.14030