Bad Astronomy

Saturn’s heat rash

I always say that (besides Earth) Saturn is the most beautiful planet in the solar system.

I may have to revise that opinion. At least in this case. It looks infected!*

That’s a Cassini image, taken in the infrared, showing a weird aurora at the ringed planet’s north pole. We’ve been observing the aurorae on Saturn for years (I remember when we got UV images of it with Hubble, about ten years ago), but nothing like this one. In general, aurorae change shape as the magnetic field of a planet fluctuates and interacts with the Sun’s solar wind. But this one doesn’t really do that. It also has been seen to fill the entire polar region of Saturn’s equivalent of the Arctic.

In the image, light at 4 microns wavelength (roughly six times longer than the human eye can see) is blue, and light at 5 microns is in red. The latter shows warm gases deep in Saturn’s atmosphere, and you can see the usual storms and other features. Usually aurorae form a ring pattern, but you can see patches of auroral emission inside the main ring, which is unexpected.

So what’s causing this weirdness? We don’t know. There is an unusual interaction going on between the Sun’s constant wind of subatomic particles, Saturn’s magnetic field, and the atmosphere of the planet. I don’t have a clue what that could be since this isn’t my field (haha, a little magnetic joke there), but we know that the weather at Saturn’s poles is a little strange. Maybe that has something to do with it. Beats me.

I’m also sure the pseudoscientists will have a field day with this one, conjuring all up kinds of nonsense to explain this away. Their chatter will die, as it always does, when science fills the gaps in our current knowledge. Well, it will mostly die; as long as there are credulous people there will always be hucksters ready to pick their pockets.

But just look at that very odd and vaguely disturbing picture of Saturn’s boreal regions, and remember that nature is odd, nature is surprising, and nature is baffling. We still don’t have all the pieces of the puzzle… but that doesn’t mean we have to cut up what we do know to make the pieces fit. Reality will release its secrets eventually. It always does.

Image credit: NASA/JPL/University of Arizona