Answer: Saturn

Scientists have long known about and studied the intense storms that whip through the atmospheres of such gas giants as Saturn and Jupiter. Despite the extended study and space probes dispatched to these distant planets, some things still remain a mystery to the astronomers monitoring them.

On Saturn there is an enormous hurricane-like storm–the eye of the storm is large enough to swallow two Earths side-by-side. Large storms are certainly nothing new on Saturn but this particular storm is a meteorological puzzle researchers will be unpacking for years. It shows no signs of dissipating; the storm has been spinning at 220 miles per hour for 30 years we’ve been observing it. Even more interesting than its size and longevity: it’s a nearly perfect hexagon. The enormous jet-streams powering the storm collide in such a fashion that the storm stays fixed in place, shaped like a giant planetary Stop sign.

Studying the storms has proven to be particularly fruitful as the jet stream movements and other meteorological phenomenon occur without resistance from a planetary surface, allowing researchers to study them in a sort of isolation unobtainable on Earth.