title: Cassini observes the active south pole of Enceladus.
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 approximately 55 degrees 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.
authors.affiliation: Cassini Imaging Central Laboratory for Operations, Space Science Institute, 4750 Walnut Street, Suite 205, Boulder, CO 80301, USA. carolyn@ciclops.org
authors.forename: C C
authors.initials: CC
authors.lastname: Porco
authors.forename: P
authors.initials: P
authors.lastname: Helfenstein
authors.forename: P C
authors.initials: PC
authors.lastname: Thomas
authors.forename: A P
authors.initials: AP
authors.lastname: Ingersoll
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authors.lastname: Wisdom
authors.forename: R
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authors.lastname: West
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authors.lastname: Neukum
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authors.initials: T
authors.lastname: Denk
authors.forename: R
authors.initials: R
authors.lastname: Wagner
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authors.lastname: Roatsch
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authors.initials: S
authors.lastname: Kieffer
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authors.lastname: Turtle
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authors.lastname: McEwen
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authors.initials: TV
authors.lastname: Johnson
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authors.lastname: Rathbun
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authors.lastname: Veverka
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authors.lastname: Wilson
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authors.lastname: Perry
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authors.initials: J
authors.lastname: Spitale
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authors.lastname: Brahic
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authors.initials: JA
authors.lastname: Burns
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authors.lastname: Delgenio
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authors.lastname: Dones
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authors.initials: CD
authors.lastname: Murray
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authors.lastname: Squyres
mesh_terms: D005118:Extraterrestrial Environment / Q000737:chemistry; D018539:Saturn; D018531:Spacecraft; D013057:Spectrum Analysis