Ground-Based Observations of Saturn's North Polar Spot and Hexagon

  title={Ground-Based Observations of Saturn's North Polar Spot and Hexagon},
  author={Agust{\'i}n S{\'a}nchez-Lavega and J. J. Lecacheux and Florent Colas and P. Laques},
  pages={329 - 332}
Ground-based observations of two conspicuous features near the north pole of Saturn, the polar vortex and the hexagonal wave structure, were made from July 1990 to October 1991, 10 years after their discovery. During this period the polar spot drifted in longitude, relative to system III, by –0.0353� per day on average. Superimposed on this mean motion, the spot also underwent short-term rapid excursions in longitude of up to ∼14� at rates of up to ∼1� per day. The spot also exhibited irregular… 
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