Lagrangian Coherent Structures from Video Streams of Jupiter

TL;DR

This paper identifies unsteady material structures in Jupiter's atmosphere, including jet cores and the Great Red Spot boundary, using video data from NASA Cassini to better understand planetary atmospheric dynamics.

Contribution

It introduces a novel application of Lagrangian Coherent Structures to analyze Jupiter's atmospheric features from spacecraft video footage.

Findings

Unsteady material structures delineate jet cores and GRS boundary.

Lagrangian analysis reveals persistent and dynamic atmospheric features.

First application of Lagrangian Coherent Structures to planetary atmosphere video data.

Abstract

Jupiter's fast rotation - one rotation over 10 hours - creates strong jet streams, smearing its clouds into linear bands of dark and light zonal belts that circle the planet on lines of almost constant latitude. Such a high degree of axisymmetry is absent in our own atmosphere. Moreover, Jupiter has the largest and longest-living known atmospheric vortex, the Great Red Spot (GRS). Such vortices abound in nature, but GRS's size, long-term persistence, and temporal longitudinal oscillations make it unique. Here, we uncover, for the first time, unsteady material structures that form the cores of zonal jets and the boundary of the GRS in Jupiter's atmosphere. We perform our analysis on a velocity field extracted from a video footage acquired by the NASA Cassini spacecraft.