10 February 2018

Saturn’s Amazing Six-Sided Hurricane

At four times the size of our pale blue dot, there is a storm raging over Saturn’s north pole – and it is six-sided. That's right - a hexagonal hurricane. How did this geometric shape come to be, what caused it? This and other questions about Saturn (great footage of the planet’s own version of the northern lights) are answered in this great video, produced by: Dennis Overbye, Jason Drakeford and Jonathan Corum.

Here are some images of this incredible phenomenon.  First, a raw Cassini image acquired on Feb. 26, 2013 which shows the planet's hexagon structure around its polar latitudes, as well as the central spinning vortex over its pole.  There is an old Latin saying -  ordo ab chao - out of chaos, comes order.  Whoever it was who first said that probably didn't have Saturn in mind.

This is a view of Saturn's north polar region, taken by Cassini's Imaging Science Subsystem (ISS) on February 26, 2013. This composite is made of images that were taken by Cassini's camera system, the Imaging Science Subsystem (ISS) on February 26, 2013 and received on Earth February 27, 2013.  At four times the size of Earth the storm is unimaginable in its ferocity.  Even one of the smaller systems either within or outside the hexagon would devastate an entire continent on Earth.

This is another composite of images taken by Cassin’s camera system, the Imaging Science Subsystem (ISS) during its "Storm Watch" observations.  They were taken on February 26, 2014 and reached Earth on February 27, 2014. The camera was pointing toward Helene, Saturn's moon which must have been behind Saturn at the time these images were taken.  Helene was named after Helen of Troy who, in Greek mythology was the granddaughter of Cronos (aka Saturn).

A color-composite image of Saturn's northern pole, made from raw Cassini images acquired November 27, 2012.  This shows the central cyclone surrounded by the wider hexagonal jet stream feature. It was first spotted by Voyagers 1 and 2 over thirty years ago.  In its epic journey around the sun, the storm has been hidden from our view and only recently become visible to us again.

Image Credit Flickr User Euclid Vandercrow
Spring has come to Saturn (it goes around the sun once every 29.4 years.  The north polar hexagon is now fully lit by the sun and many other smaller storms are dotted around.  You can see the rings of Saturn disappearing behind its own shadow in the background.

The image was taken with the Cassini spacecraft's wide-angle camera on November 27 2012 using a spectral filter sensitive to wavelengths of near-infrared light centered at 750 nanometers.

The spacecraft was approximately 403,000 miles (649,000 kilometers) from Saturn at the time.

Image Credit Val Klavens
This is a true color view of Saturn's north polar region, taken by Cassini's Imaging Science Subsystem (ISS) on June 26, 2013. You can see Saturn's mysterious hexagon in the center. The images reached us the next day (making it better than many Earth-bound postal delivery services I dare say). The camera was pointing toward Saturn at approximately 402,383 miles (647,573 kilometers) away. It may sound like a long way from the planet but in terms of the distance Cassini had already traveled, this must count as an extreme close-up.