Scientists used to think that things were pretty chill over in the south hemisphere of Uranus. In fact, they thought it was one of the calmest regions of any of the gas giants. But in analyzing images taken nearly three decades ago by NASA's Voyager-2 spacecraft, researchers think they've found a kerfuffle of activity — which might indicate that there's something unusual about the planet's interior. If you look at these old photos of Uranus, the planet appears to be a stark, featureless ball. And even to scientists, who were able to identify more lively features of the gas giant,...