Cassini Observes the Active South Pole of Enceladus
Burns, J. A.; Neukum, G.; Wagner, R.; Denk, T.; Porco, C. C.; Brahic, A.; Murray, C. D.; Spitale, J.; Roatsch, T.; West, R.; Dones, L.; Turtle, E.; McEwen, A.; Del Genio, A. D.; Helfenstein, P.; Ingersoll, A. P.; Johnson, T. V.; Perry, J.; Squyres, S.; Veverka, J.; Thomas, P. C.; Wilson, D.; Wisdom, J.; Kieffer, S.; Rathbun, J.
United States, Germany, France, United Kingdom
Abstract
Cassini has identified a geologically active province at the south pole of Saturn's moon Enceladus. In images acquired by the Imaging Science Subsystem (ISS), this region is circumscribed by a chain of folded ridges and troughs at ~55°S latitude. The terrain southward of this boundary is distinguished by its albedo and color contrasts, elevated temperatures, extreme geologic youth, and narrow tectonic rifts that exhibit coarse-grained ice and coincide with the hottest temperatures measured in the region. Jets of fine icy particles that supply Saturn's E ring emanate from this province, carried aloft by water vapor probably venting from subsurface reservoirs of liquid water. The shape of Enceladus suggests a possible intense heating epoch in the past by capture into a 1:4 secondary spin/orbit resonance.