The composition and structure of Enceladus' plume from the complete set of Cassini UVIS occultation observations

Abstract Observations acquired at ultraviolet wavelengths are uniquely well-suited to investigate the composition and structure of Enceladus' plume. This paper describes the observations, analysis techniques and results of all the Enceladus occultations observed by Cassini's Ultraviolet Imaging Spectrograph (UVIS) and other observations designed to study the plume. Limits on gas at non-polar latitudes are derived. Constraints on the minor constituents' composition of Enceladus' primarily water vapor plume are evaluated. The overall source rate variability over a time span of 13 years is

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