There’s Something About Saturn

Saturn’s mammoth, six-sided storm.
Saturn’s mammoth, six-sided storm.

There’s something to be said for Saturn. The solar system’s most “photogenic planet” as the New York Times cosmic correspondent Dennis Overbye, puts it, has weird weather, for one.

A Six-Sided Storm. Our tropical storms, when they’re bad enough, make us wince. But they’re pipsqueaks compared to what rages on this giant beauty. When Voyager swung by it around 1980, it’d clapped eyes on a strange phenomenon on it.

Unlike our own Arctic, the Saturnian north pole isn’t a serene region, but one of severe atmospheric disturbance, roiled by a humongous, hexagonal hurricane that looks like a magically majestic invention, conjured by Salazar Slytherin.

The six-sided vortex of towering clouds, blazing lightning, and eddying gases has an eye roughly 1,250 miles across—about 20 times the size of a typical storm back home—and can engulf four Earths.

As Saturn takes 29.5 years to make one spin around the Sun, its seasons, too, are correspondingly longer than ours. In 2004, when its winter began to withdraw and spring dawned, Cassini was around to take an up-close look at this behemoth cyclone.

Diamonds Aren’t Forever. If we could see Saturn’s gaseous sky, would it appear sooty? The banks of clouds in the upper reaches of its atmosphere have in them pale methane, which is whipped up into fluffy carbon globs by furious, Thor-worthy thunderbolts.

Then, as they hurtle downward, they’re compressed. After passing through about 1,000 miles, they harden, changing into sheets of graphite—the form we see it in our pencils.

Deeper still, at about 3,700 miles, these nubs toughen into dazzling little stones, big enough to set as a solitaire in a gold ring. Only, they’re uncut and unpolished. Kevin Baines of the University of Wisconsin at Madison and NASA’s Jet Propulsion Laboratory told the BBC that Saturn generates about 1,000 tons of the sparkling stuff a year.

But these diamonds don’t last forever. By the time they plummet through another 18,600 miles or so, the pressure and temperature becomes so infernal that they lose their solidity.

It’s uncertain what happens, next, but one possibility is that they melt into a bubbling, black sea. Possibly, they have greater guarantee of staying as precious gems on Uranus and Neptune, which have colder cores.

Not Quite The Four Seasons. Saturn’s largest Moon, Titan, is a doozy. It’s the only moon in this neck of the cosmic woods to have a thick, hazy atmosphere. Its air, like ours, is rich in nitrogen, but unlike ours, which also has life-sustaining oxygen and water, Titan has a mix of hydrocarbons.

It’s the only other place outside Earth that harbors liquids on its surface—in the form of methane lakes. Under its icy shell, it even hides away a briny ocean of water.

Because of its axial tilt, it’s known to have seasons. What’s not to like about Titan? A prime driver of its weather is methane, one of the so-called greenhouse gases. But the cycle of evaporation and precipitation on it is very similar to that of Earth’s.

There’s a saying in Minnesota that goes like this: “If you don’t like the weather—wait a day and it’ll change.” Titan isn’t like Minnesota. The weather on this chilly (about minus 292 degrees Fahrenheit) and smoggy world takes time to change.

But toward the end of July, Cassini detected the buildup of a cloud cover over Titan’s second-largest lake, Ligeia Mare (pronounced: “MAR-ay,” meaning “sea” in Latin.) As though driven by winds, they appeared to scud away across the orangish sky at as fast as 10 m.p.h.

Planetary researchers wonder if this development signalizes a change of season and the arrival of summer or if it’s a puzzling anomaly. Computer models forecast more clouds—but with no chance of meatballs.

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