“More days to come / New places to go
I’ve got to leave / It’s time for a show
Here I am / Rock you like a hurricane!” –The Scorpions
It isn’t just Earth, of course, where these great cyclonic storms occur, whipping across the planet and wreaking havoc as they rage above the surface. Most famous, perhaps, is Jupiter, whose great red spot has existed for as long as we’ve been able to see at the necessary resolution.
But one doesn’t often think of Saturn when it comes to devastating storms.
Saturn, quite famously, is a great gas giant planet, second only in size to Jupiter in our Solar System, and renowned for its spectacular rings. And although Saturn’s rings are its most obvious feature, the clearly defined, featureless bands along its different latitudes also stand out.
Unless, that is, you’ve taken a close look in the last year or so.
That is not a featureless band up there in Saturn’s Northern Hemisphere!
Quite to the contrary, this is a virtually planet-wide storm plume, whose core is a 3,000-mile-wide thunderstorm, kicking up beacons of warm air and leaving behind ammonia ice crystals, which we can tell from Cassini‘s observations in the infrared.
Cassini, the famed Saturn spacecraft that’s been orbiting our ringed neighbor for nearly a decade, first spotted this storm in the earliest stages of its infancy, all the way back in early December, 2010. I’ve highlighted it, below, visible right at Saturn’s terminator.
Unlike storms on Earth, which typically last for days or — in particularly devastating cases — a few weeks, this storm on Saturn has set a new record.
Lasting for more than 200 days, this Saturnian tempest rages all the way into August of last year, with the storm’s head lasting intact at least into May. This made it the longest-lasting storm of this kind ever seen on Saturn; the first one since 1990 and the longest one since the first one was ever observed, all the way back in 1876!
As you can see, it was so powerful that, from February to April, the storm actually lapped itself, with the head of the storm clearly visible in those images.
What you might not realize is that Cassini was also able to clearly identify the tail of the storm, by looking in the infrared! Below, in false-color, the red-orange methane clouds are topped by a high blue haze signifying the main end of the tail. (The rings also appear in blue as a thin line, as there is no methane there at all!)
Although this is all that NASA released, Cassini is a bit of a special mission. You see, they have a publicly accessible imaging diary over at Cassini Imaging Central Laboratory for OPerationS (CICLOPS).
Want to see how the storm changed from one (Saturnian) day to the next? Taken 11 hours apart, from February 23rd, 2011 to February 24th, you can really see that — at a scale of 64 miles (104 km) per pixel in the below image — this giant hurricane is migrating across the face of Saturn at around 100 km/hr!
And finally, what can Cassini do, at its highest resolution in (nearly) true color, looking at the storm as it traverses its own wake across the planet? Click on the image for full-resolution, but even at its reduced screen resolution… well, see for yourself!
You can follow the entire saga of the Saturn Storm Chronicles‘ report on last year’s record-breaking display over at CICLOPS, but what an amazing view from Cassini!