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arXiv · 1407.4072

Lagrangian Coherent Structures from Video Streams of Jupiter

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.

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Alireza Hadjighasem, George Haller. 2014-07-15. Lagrangian Coherent Structures from Video Streams of Jupiter. https://arxiv.org/abs/1407.4072

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