Hyperion's sponge-like appearance

  title={Hyperion's sponge-like appearance},
  author={Peter C. Thomas and J. W. Armstrong and Sami W. Asmar and Joseph A. Burns and T. Denk and Bernd Giese and P. Helfenstein and Luciano Iess and Torrence V. Johnson and Alfred S. McEwen and Line S Nicolaisen and Carolyn C. Porco and Nicole J. Rappaport and James E. Richardson and L. Somenzi and Paolo Tortora and Elizabeth P. Turtle and Joseph Frank Veverka},
Hyperion is Saturn’s largest known irregularly shaped satellite and the only moon observed to undergo chaotic rotation. Previous work has identified Hyperion’s surface as distinct from other small icy objects but left the causes unsettled. Here we report high-resolution images that reveal a unique sponge-like appearance at scales of a few kilometres. Mapping shows a high surface density of relatively well-preserved craters two to ten kilometres across. We have also determined Hyperion’s size… 

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