Photometric and spectral analysis of the distribution of crystalline and amorphous ices on Enceladus as seen by Cassini

Abstract

Photometric and Spectral analysis of data from the Cassini Visual and Infrared Mapping Spectrometer (VIMS) has yielded intriguing findings regarding the properties and composition of the surface of Saturn's satellite Enceladus. Spectral cubes, which contain both spatial and spectral information, were obtained of this satellite with a wavelength distribution in the infrared far more extensive than from any previous observations and at much higher resolution. Using these cubes, we have discovered a distribution of amorphous and crystalline ices on the southern pole of Enceladus, indicating intense ion bombardment in those latitudes and recent geological activity at the "tiger stripe" cracks. Using a composite mosaic of the satellite, we map this distribution of ices according to a "crystallinity factor" and consider investigation of the time scale of the geologic activity based on amorphization rates in the outer solar system.