Bad Astronomy

Saturn’s gorgeous gray mood

I love the splashy full-color pictures of Saturn, but sometimes grayscale (or what is commonly, and incorrectly, called black-and-white) is what’s needed to capture a mood. Take a look at Cassini’s latest view of the ringed planet:

Sigh. Oh my. Click to enjovianate.

If Saturn looks a little different here it’s because this image isn’t made with visible light. The light we can see with our eyes is easily absorbed by Saturn’s atmosphere, so when we look at Saturn we only see the very tops of the clouds. But this picture was made with infrared light, which can come from deeper in Saturn’s thick atmosphere and pass through the upper layers unimpeded. This allows us to see the delicate patterns of the planet’s banding, making it look more like its big brother Jupiter. Note the incredibly beautiful swirl in the lower part, curling up into what looks almost like Jupiter’s Red Spot! But don’t let its grace and beauty fool you: all those curves and whorls are storms with winds moving at hundreds of kilometers per hour, dwarfing any mere terrestrial hurricane.

Pictures like this remind us that Saturn is a dynamic world in and of itself, more than just a host for rings.

But still, the rings really are cool. This picture was taken when Cassini was almost perfectly in the plane of the extremely thin rings, so they look like a bright line across the planet. The dark stripes below are actually the shadows of the rings! You can even easily see the gaps in the rings, where the ice particles have been swept clear by the gravity of Saturn’s fleet of moons.

I’m not an expert in planetary atmospheres or ring systems, and I’ve learned a lot over the years by looking at these images, reading the papers, and talking with the Cassini imaging team leader Carolyn Porco. I’ll never understand the planet as well as she does, or the dozens, hundreds of scientists who make up the team responsible for analyzing Cassini’s data. But that’s OK: I know they’ll be kept busy for decades poring over images like these, and it’s a good thing when scientists are busy.

And, of course, those of us looking in from the outside get to see breathtaking pictures of the solar system’s loveliest planet. All in all, it’s a pretty good deal for everyone.

Tip o’ the F Ring to Carolyn Porco. Image credit: NASA/JPL/Space Science Institute