Silicates versus Sulphur - Searching for Clues about Ionian Vulcanism with Canaricam

Vulcanism was rst detected on Io in 1978 by Voyager 1. Since then it has been recognised that Io is the most volcanically active body in the Solar System. Although the initial volcanic activity observed was in the form of SO2 geysers and sulphur lakes, the Galileo mission has detected temperatures as high as 1800K on the surface, far in excess of the temperatures that can be explained by sulphur-driven activity. Galileo observa- tions suggest that silicate vulcanism is the principal driver of activity, even though the temperatures measured are even in excess of those measured in terrestrial silicate vul- canism, but the relationship between silicate and sulphur-driven activity is not well un- derstood. We propose a project to monitor low-temperature vulcanism on Io systemat- ically, using CanariCam on the GTC. This project will allow a better understanding of the mechanisms of sulphur-driven vulcanism, and the relative importance of silicate and sulphur-driven activity.