An enduring rapidly moving storm as a guide to Saturn's Equatorial jet's complex structure.
Where this comes from
- Record sourced from PubMed, PMID 27824031.
- Also identified by DOI 10.1038/ncomms13262 and PMC identifier 5105178.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Saturn has an intense and broad eastward equatorial jet with a complex three-dimensional structure mixed with time variability. The equatorial region experiences strong seasonal insolation variations enhanced by ring shadowing, and three of the six known giant planetary-scale storms have developed in it. These factors make Saturn's equator a natural laboratory to test models of jets in giant planets. Here we report on a bright equatorial atmospheric feature imaged in 2015 that moved steadily at a high speed of 450 ms<sup>-1</sup> not measured since 1980-1981 with other equatorial clouds moving within an ample range of velocities. Radiative transfer models show that these motions occur at three altitude levels within the upper haze and clouds. We find that the peak of the jet (latitudes 10° N to 10° S) suffers intense vertical shears reaching +2.5 ms<sup>-1</sup> km<sup>-1</sup>, two orders of magnitude higher than meridional shears, and temporal variability above 1 bar altitude level.