The Equatorial Ridges of Pan and Atlas: Terminal Accretionary Ornaments?

+ See all authors and affiliations

Science  07 Dec 2007:
Vol. 318, Issue 5856, pp. 1622-1624
DOI: 10.1126/science.1148631

You are currently viewing the abstract.

View Full Text


In the outer regions of Saturn's main rings, strong tidal forces balance gravitational accretion processes. Thus, unusual phenomena may be expected there. The Cassini spacecraft has recently revealed the strange “flying saucer” shape of two small satellites, Pan and Atlas, located in this region, showing prominent equatorial ridges. The accretion of ring particles onto the equatorial surfaces of already-formed bodies embedded in the rings may explain the formation of the ridges. This ridge formation process is in good agreement with detailed Cassini images showing differences between rough polar and smooth equatorial terrains. We propose that Pan and Atlas ridges are kilometers-thick “ring-particle piles” formed after the satellites themselves and after the flattening of the rings but before the complete depletion of ring material from their surroundings.

View Full Text

Related Content