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Cassini Probes the Hexagon On Saturn
Riding with Robots sends us to a NASA page with photos of a little-understood hexagonal shape surrounding Saturn's north pole. "This is a very strange feature, lying in a precise geometric fashion with six nearly equally straight sides," said Kevin Baines, member of Cassini's visual and infrared mapping spectrometer team. "We've never seen anything like this on any other planet." This structure was discovered by the Voyager probes over 20 years ago (here's an 18-year-old note on the mystery). The fact that it's still in place means it is stable and long-lived. Scientists have no idea what causes the hexagon. It's nearly big enough to fit four earths inside — comfortably larger than Jupiter's Great Red Spot. The article has an animation of clouds moving within the hexagon captured in infrared light.
'Nuff said.
Another related possibility is spherical harmonics, similar to what happens in the sun. The planet would be effectively resonating like a 3D drumhead. If that's true, there should be other points on the surface that exhibit similar phenomena.
ceci n'est pas une
The curious thing, though, is that the south pole is very different -- almost looks like a human eye. I wonder what sort of rotational effect could cause such an asymmetry between north and south poles?
How come things that happen to stupid people keep happening to me?
Well, after doing some actual research on this, it looks like there are some possible contributors to spherical harmonics on Saturn, but that probably isn't the source of the hexagonal structure, since a similar structure does not appear at the south pole. Apparently it's probably due to a polar jet, similar to the ripples you see around a bathtub drain.
ceci n'est pas une
So isn't this phenomenon the orbital equivalent of an wave interference pattern? You have a whole bunch of particles in cirulation with slight differences in the size, shape, and eccentricity of their paths, and the result is a polygon-shaped interference pattern. Just like the polygons created by the purely circular motions of a Spirograph.
Fritjov Capra ( this guy's an absolute legend, by the way ) had an interesting section on hexagonal structures like these in his book, Web of Life. He was talking about Dissipative Structures, discovered by Ilya Prigogine.
... ie you could run a pen through them and disturb them, and they'd immediately revert to these perfect hexagons. It was fascinating reading - thoroughly recommended for people interested in biology, physics, and philosophy.
In the experiment that was being described, a small dish of water was heated up uniformly from below. At a certain point, these hexagonal structures emerged. Hot water would rise from the bottom of the dish, travelling in a pipe directly through the middle of the hexagon ( forming a point in the middle that you could see ). When the water hit the surface, it spread out cooled, and then travelled back down to the bottom, creating the sides of the hexagon. Apparently they were getting multiple hexagons, and they were incredibly stable
I was under the impression that this is part of the wargame project that put SPI out of business.
(SPI?!? see http://www.costik.com/spisins.html )
as seen here: http://www.etl.noaa.gov/about/eo/science/convectio n/RBCells.html
Not sure how the rotation affects/interacts with those.
...the future crusty old bastards are already drinking the Kool-Aid.
If our solar system contains so many mysteries, imagine what the rest of the universe holds.
Imagine the scientific excitement if you were aboard a vessel like the Galaxy Class USS Enterprise from Star Trek (NCC 1701 D), approaching Saturn and seeing live the phenomenon, then staying there for a while to study it and comprehend it!
Exploration of space is the most important goal for humankind. Earth provides a very limited experience, and in a few 100 years it will be totally explored. If we want to understand the universe, space is the final frontier.