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Saturn's North Pole Is A Hexagon, And No One Knows Why (nasa.gov)
144 points by PhearTheCeal on Feb 23, 2013 | hide | past | favorite | 27 comments

Reseachers were able to model this in the lab:


I can posit a theory:

A hexagon is a boundary shape with the least energy. What you are really probably seeing is a circle that has pushed outwards against another set of forces and reached equilibrium (differing temperatures, gasses, who knows what). I have been playing with voronoi diagrams and diffusion limited aggregation recently , and it is amazing some of the structures that will emerge when a system reaches equilibrium. It is possible that certain forces have aligned with their peak energies in the form of a regular polyhedra, which happens all over nature on large and small scales.

I find it hard to imagine what dynamics could give rise to a regular shape that's not a circle. Could you elaborate?

Its "common knowledge" that standard twist drills sometimes cut stable polygons instead of perfect circles if its a wimpy metal for the drill and a tough metal for the work (which is why woodworkers don't see this often). Thats why machinists rough cut a hole with a standard twist drill about 1/32 small then ream to precise diameter. Take something wiggly-ish thats X units long and it'll tend to catch in a corner, then sweep out a radius of X units until it slips free (and typically gets stuck in the next corner). Unfortunately this is stable and self reinforcing. Hexagons and higher order polygons are pretty rare usually you get somewhat oversize triangle-ish shaped hole. Yes the sides are not precisely flat they are curved.

So the above is a factual statement of reality. A wild conjecture is this metalworking effect might be a physical manifestation of what the OP is talking theoretically about. A further (pair of?) wild conjecture is either my example or the OPs example could have something to do with saturn's hexagon. I would not be completely surprised if there is a numerological oscillation set up where 1/6th (or 1/3rd) of a planetary rotation is exactly long enough for prevailing winds or a sonic boom or something like that to cross the diameter of the hexagon. Or we're seeing a weird phase change trick as "something" evaporates and condenses in response to a rolling atmospheric high pressure zone.

There's also a circle packing argument where at a deeper atmospheric layer than we can see, there's six rotating vortexes which just fit within the hex.

All I can say is I'm thankful its a stable 6-agon instead of a stable 5-agon or we'd never hear the end of it from the nutcases.

Try packing circles as closely together as possible. You will see that the best packing has one circle in the center with 6 circles around it. https://en.wikipedia.org/wiki/Circle_packing#Packings_in_the... If each circle then expands equally to fill the gaps, you will end up with a bunch of hexagons. https://www.youtube.com/watch?feature=player_detailpage&...

Well, crystals would be obvious example.

There are a number of fluid dynamic studies that show 'angled' flow, generally around mixed densities and viscositys coming into contact with each other. That said, its a cool effect.

If it were science fiction there would be a giant hexagonal shaped structure under the clouds on the pole. Waiting ...

It's God's own hex nut.

Don't take it off! Saturn will fall off and go wobbling around the Solar System.

There - intelligent design, the evidence.

This kind of design doesn't strike me as very intelligent.

You just lack a God-like perspective, is all.

We can't be having with Sloppy Saturns.

>It turned out that the rate of ring rotation changed the shape of the pattern from a circle to just about anything, including ovals, triangles, squares and various polygons.

Wow. Imagine if it were a square on Saturn. I think that would provide more fodder for sci fi writers than the hexagon.

You can build hexagons really easily out of equilateral triangles, which seems even purere than squares to me.

http://www.bioedonline.org/news/news.cfm?art=2531 Researchers at the Technical University of Denmark in Lyngby have created similar geometric shapes (holes in the form of stars, squares, pentagons and hexagons) in whirlpools of water in a cylindrical bucket.

The website has an awkwardly placed link.

The link mentions "Saturn's South Pole … with its rotating vortex" with a link to another post from the website with a picture of the vortex, but the description is that of "the north pole of Saturn… [a] vortex of strange and complex swirling clouds" encompassed in a hexagon.

Do we have pictures of the south pole?

Found one by clicking "rotating vortex" > "infrared images" > "rotating vortex": http://apod.nasa.gov/apod/ap061113.html . I guess someone got lazy.

The video attached to the link, "huge vortex rotating" on that Saturn page is... not exactly what I expected.

I bet on http://en.wikipedia.org/wiki/Faraday_wave : The waves can take the form of stripes, close-packed hexagons, or even squares or quasiperiodic patterns. See also http://nanopatentsandinnovations.blogspot.de/2012/11/new-typ...

Reminds me of the 1986 novel Saturnalia - http://en.wikipedia.org/wiki/Saturnalia_(Callin_novel) - in which the aliens who leave calling cards in the moons of Saturn are called "hexies" because they use so many 6's in their messages.

What about Rayleigh–Bénard convection?

"Convective Bénard cells tend to approximate regular right hexagonal prisms, particularly in the absence of turbulence"


Clearly it must be that Saturn is a truncated icosahedron or similar. it was probably laser-cut by the aliens in the galactic planet factory.


But they won't be so smug when the rest of the hive is completed....

But perhaps they don't know they know?

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