APOD: Saturn's North Polar Hexagon (2018 Sep 07)

[APOD Robot]

Saturn's North Polar Hexagon

Explanation: In full view, the amazing six-sided jet stream known as Saturn's north polar hexagon is shown in this colorful Cassini image. Extending to 70 degrees north latitude, the false-color video frame is map-projected, based on infrared, visible, and ultraviolet image data recorded by the Saturn-orbiting spacecraft in late 2012. First found in the outbound Voyager flyby images from the 1980s, the bizarre, long-lived feature tied to the planet's rotation is about 30,000 kilometers across. At its center lies the ringed gas giant's hurricane-like north polar storm. A new long term study of Cassini data has found a remarkable higher-altitude vortex, exactly matching the outlines of the north polar hexagon, that formed as summer approached the planet's northern hemisphere. It appears to reach hundreds of kilometers above these deeper cloud tops, into Saturn's stratosphere.

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[madtom1999]

Is it a hurricane or is it an anti-cyclone driven by the cold gas falling down the central hole towards the centre of the planet?

[heehaw]

...falling down the central hole towards the centre of the planet?

https://www.mirror.co.uk/news/weird-new ... le-8019446

[Ann]

...falling down the central hole towards the centre of the planet?

https://www.mirror.co.uk/news/weird-new ... le-8019446

Click to view full size image

Source: https://www.barnesandnoble.com/w/journe ... 1104880805#/

Click to view full size image

Source: https://www.discogs.com/Rick-Wakeman-Jo ... se/8605985

Well, it might be easier to reach the center of Saturn than the center of the Earth.

Maybe. Who knows?

Ann

[orin stepanek]

Looks like a pearl from a string of beads!

[Imagineer]

Appearing with the massive hexagon and center vortex are a few other features or artifacts in the false-color map-projected video image that are not mentioned/explained.
1) A small dark speck at the very edge of the image ~4 o'clock,
2) A much larger light shaded disk at ~5:30,
3) A light-dark boundary ~7:00, and
4) A bright narrow cyan-colored ellipse adjacent to a similar sized more muted magenta ellipse at ~9:00.
Both items 2 and 4 are relatively near lobes of the hexagon.

[Iksarfighter]

Actually its an hexagon. Maybe sometimes its an octogone or a square or other thing.

[bystander]

viewtopic.php?t=38661

[BDanielMayfield]

The following is a joke. It is only a joke. Do not, under any delusional thinking, doubt that it is anything other than a joke:

It's a docking port for the ships of gas giant aliens.

Bruce

[suicidejunkie]

I think you might be stretching there, Bruce.
It is clearly just the peg-hole from somebody's full-scale Orrery.

[Guest]

I ran a simulation of this, based on published data and theories. I noted that the hexagon, and seen in three dimensions in the context of the hexagon, seems to show an internal rotation in the counter clockwise direction. like currents in a river. I examined the image posted and that seems to be indicated visually. Kind of like a twisting rope.

[BDanielMayfield]

I think you might be stretching there, Bruce.
It is clearly just the peg-hole from somebody's full-scale Orrery.

Ok, that's a just as [un]reasonable theory.

But, otoh it could explain much. The invisible apparatus is what scientists call dark matter, and it's kept wound up by dark energy.

[justicelarry@ymail.com]

Maybe,

The reason the flow around Saturn's north pole is a hexagon rather than a circle is that the six legs of the hexagon is a shorter path than a complete circle would be and the currents can move faster, more in tune with the speed the Saturn weather wants them to go.

Thanks,
Amateur at work

[neufer]

Cyclones at Jupiter's North Pole

Explanation: Juno's Jovian Infrared Auroral Mapper data was used to construct this stunning view of cyclones at Jupiter's North Pole. Measuring the thermal emission from Jovian cloud tops, the infrared the observations are not restricted to the hemisphere illuminated by sunlight. They reveal eight cyclonic features that surround a cyclone about 4,000 kilometers in diameter, just offset from the giant planet's geographic North Pole. Similar data show a cyclone at the Jovian South Pole with five circumpolar cyclones. The South Pole cyclones are slightly larger than their northern cousins. Cassini data has shown that gas giant Saturn's north and south poles each have a single cyclonic storm system.

[neufer]

Click to play embedded YouTube video.

[Boomer12k]

That is just awesome!

We should call it... The Polar ROSE of Saturn... "The Polar Rose of Saturn, isss...the only rose for meeee..."

I was a 3rd year Music Major...you know it is going to be a big hit....

:---[===] *

[MarkBour]

When looking at the image for today's APOD, it is helpful to note that the image has been cropped with a circular edge. The image has "zeroed in" on the hexagon. The circular edge is nowhere near the outer edge of the planet. The unusual cropping of the image might give some viewers the impression that this hexagon is much larger and more dominant of the polar region than it is.

A fuller view of the storm on Saturn is at the right.

Of course it is still a gigantic feature, larger in radius than the Earth.

But I find it very difficult to imagine this shape as being stable if it were significantly larger on the spherical surface of Saturn than it is.