Here in Rochester, it is easy to lament the long transition from winter into summer. Not only long, but inconstant and subject to depressing changes that leave us shivering in our spring clothing. Still, as seasonal changes go, one can hardly compare our Earth’s cycle to that of the Saturnian moon Titan, where the change takes seven years.
Scientists studying Titan have observed an ice cloud that hovers over Titan’s northern hemisphere for some time. But as the seasons change on Titan and the wind patterns begin to shift, that ice cloud has shifted southward in a process similar to Earth’s own Hadley cell. This seasonal change on Earth is closely associated with our jet streams:
At first blush, the southern ice cloud seems to be building rapidly. The northern ice cloud, on the other hand, was present when Cassini first arrived and has been slowly fading the entire time the spacecraft has been observing it.
So far, the identity of the ice in these clouds has eluded scientists, though they have ruled out simple chemicals, such as methane, ethane and hydrogen cyanide, which are typically associated with Titan. One possibility is that “species X,” as some team members call the ice, could be a mixture of organic compounds.
So there you have it: Rochester weather may be cold and damp when we least like it, but at least we have a 365 day cycle. And that’s not nothin’…