A deep, hexagon-shaped feature lies above Saturn’s north pole, newly released images from the Cassini spacecraft reveal. The strange structure appears to be nearly stationary and may be a wave that stretches deep into the giant planet’s atmosphere.
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“This is a very strange feature, lying in a precise geometric fashion with six nearly equally straight sides,” says team member Kevin Baines of NASA’s Jet Propulsion Laboratory in Pasadena, California, US. “We’ve never seen anything like this on any other planet.”
Bizarre hexagon circles Saturn’s north pole (New Scientist, with animated GIF)
Update: What the Hex Going on at Saturn’s Pole? (SciAm Observations)