For their study, Griffith and colleagues analyzed near-infrared light emitted by Titan. Such spectral analyses can show what elements and compounds are present, and in what amounts. They found a lot of methane in the atmosphere, and found its presence waxed and waned. One large fluctuation looked like nothing so much as a hurricane-sized cloud system. One mystery is how the clouds and weather systems form.
Titan spins slowly, providing little vorticity to cloud systems.
In addition, Titan receives about 100 times less power from the sun. And no one knows yet just what goes on at the surface of Saturn's moon. The mysterious instigator of activity in this cool and slothful atmosphere will be examined with future ground-based observations and by the Cassini spacecraft encounter with Titan in 2004. Ralph Lorenz of the University of Arizona in Tucson said ultraviolet light from the Sun should be burning off the methane in Titan's atmosphere. But he said the report paints an interesting picture of what Titan's drizzle might look like.