With its thick atmosphere, rippling lakes, and eroded landscapes, Saturn’s giant moon Titan has a lot in common with Earth. In August scientists added another similarity shared by these unlikely siblings: stormy weather. Using the NASA Infrared Telescope Facility and Gemini North Observatory, planetary scientist Emily Schaller of the University of Arizona identified a massive storm that appeared near Titan’s equator. “For so long, it was cloud-free,” says Schaller, who devoted her doctoral research to a largely fruitless search for Titanic clouds. “Then, all of a sudden, they dramatically appeared.”
Schaller’s team could not confirm whether precipitation fell, but other studies have offered strong evidence that methane clouds on Titan dump methane rain in a cycle much like the exchange of water between the atmosphere and the surface of Earth. The scientists are now trying to determine whether Titan’s storm resulted from atmospheric conditions or from surface activity, such as methane-spewing geysers or volcanoes.