Work

Survey and Modeling of Windblown Ejecta Deposits on Venus

Year: 2025

Type: article

Abstract: Venus' thick atmosphere rotates in the same direction as the solid body, but ∼60 times faster. This atmospheric superrotation has produced dozens of windblown ejecta deposits (“parabolas”) on the surface of Venus. The formation and modification of parabolas is an interplay between impacts, aeolian modification, and atmospheric dynamics. We conducted a survey to explore the nature of these sedimentary surface features. First, we observe trends in parabolas' morphology that shed light on how they are deposited and gradated. Changes in the size and radar albedo of parabolas are likely linked to the height and density (respectively) of ejecta plumes at time of formation. Next, we discovered that parabolas show orientations inconsistent with present atmospheric dynamics. This discrepancy may record a change in these dynamics or geologically recent true polar wander at a rate of ∼1° Myr −1 , which is similar to that observed on Earth over the past century. These results highlight how overlapping observations at different radar wavelengths provide important insights into the history and character of geologic processes on Venus. Overall, atmospheric superrotation has probably persisted for at least the age of Venus' surface.

Source: AGU Advances

DOI: 10.1029/2025av001906

Authors: T. J. Austin, J. G. O’Rourke, N. Izenberg, E. A. Silber

Institutions: Arizona State University, Johns Hopkins University Applied Physics Laboratory, Sandia National Laboratories

Language: English

Topic: Planetary Science and Exploration

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,460

Funder: National Aeronautics and Space Administration