The Cassini spacecraft has found many wonders on and around the planet Saturn. Especially at the north pole (NASA Article).
One of the more perplexing and exciting discoveries was the hexagon and the scientifically unexpected aurora over it (Saturn's Poles). And that was found after a hot spot was unexpectedly found in the center of the totally unexpected hexagon.
It was first discovered two decades ago by an early mission to Saturn. It was seen again in the 1990's and now Cassini has photographed it up close and personal.
As it is studied more and more questions tend to arise. How does a hexagon shape get formed? And how does it then remain over the years in 300 mph hurricane and tornado force winds? Especially in Saturn's heavy atmosphere?
It is quite unlike the more famous Giant Red Spot on Jupiter, which is a hurricane shaped and more circular object as one would expect.
It shows once again, as we throw out the textbooks and print new ones, that our knowledge of the solar system and the universe is limited (Discovery Channel Article [it got lost, so Wayback Machine Version]).