Strange New World
On January 14 a saucer-shaped spacecraft weighing 320 kilograms made the “splat” heard round the solar system. The successful landing of the Huygens probe on Titan, Saturn’s large and mysterious satellite, delighted planetary scientists, who thrilled at the probe’s images of icy ridges and dark, riverlike channels. In the following weeks, though, the euphoria turned to head-scratching as researchers struggled to decipher the data collected by the probe. Although the four-hour-long mission provided the first close look at Titan’s surface and atmosphere, Huygens raised at least as many questions as it answered....