Cassini observes the active south pole of Enceladus.

نویسندگان

  • C C Porco
  • P Helfenstein
  • P C Thomas
  • A P Ingersoll
  • J Wisdom
  • R West
  • G Neukum
  • T Denk
  • R Wagner
  • T Roatsch
  • S Kieffer
  • E Turtle
  • A McEwen
  • T V Johnson
  • J Rathbun
  • J Veverka
  • D Wilson
  • J Perry
  • J Spitale
  • A Brahic
  • J A Burns
  • A D Delgenio
  • L Dones
  • C D Murray
  • S Squyres
چکیده

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.

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عنوان ژورنال:
  • Science

دوره 311 5766  شماره 

صفحات  -

تاریخ انتشار 2006