Oh man. It’s stuff like this that got me into space blogging in the first place.
Landing here on Earth last night, this is one of several new raw images from Cassini acquired yesterday (Nov. 27) showing the enormous cyclone of clouds swirling around Saturn’s geographic north pole. The angle of sunlight highlights the multilayered structure of the cyclone and surrounding cloud bands wonderfully… this is a roiling feature approximately 3-4,000 km across and in places appears to carve cloud channels hundreds of kilometers into Saturn’s atmosphere. Simply. Beautiful.
It’s been a while since we’ve gotten such a good look at Saturn’s north pole… over four years ago, I’d say, and in fact one of my very first blog posts here on LITD was of the hexagonal feature ringing Saturn’s northern hemisphere. Thanks to Cassini’s new orbital trajectory, which is taking it high over the ring plane and poles of Saturn, we have the opportunity to view the gas giant’s upper latitudes again.
In fact we even have a brand new look at the hexagon, which is still there, four years later:
Made of a band of upper-atmospheric winds, for some reason at this latitude the jet stream forms a six-sided hexagonal shape. The entire structure is about 25,000 km across — large enough for four Earths to fit inside! The polar cyclone can be seen at the center.
First seen by Voyagers 1 and 2 over 30 years ago, the hexagon appears to be fixed with Saturn’s rotation rate.
“This is a very strange feature, lying in a precise geometric fashion with six nearly equally straight sides,” said atmospheric expert and Cassini team member Kevin Baines back in 2007. “We’ve never seen anything like this on any other planet. Indeed, Saturn’s thick atmosphere where circularly-shaped waves and convective cells dominate is perhaps the last place you’d expect to see such a six-sided geometric figure, yet there it is.”
These are some of the most amazing images to come in from Cassini in a long time — which is no small statement about a spacecraft that has been tirelessly returning incredible images from Saturn since 2004!
One of the most valuable aspects of having a spacecraft in orbit around Saturn for such an extended period is the ability to see how the planet changes seasonally over the course of its year, which is 29.4 Earth years long.