’s Revolutionary Titan Landing

Abstract

Ten years ago, in our solar system far, far away, a spacecraft orbiting Saturn dispatched a small probe to an unexplored world—the moon Titan—an achievement that set off a space exploration revolution. The European Space Agency’s Huygens probe, carried by the National Aeronautics & Space Administration’s Cassini spacecraft, proceeded to land on Titan, which is Saturn’s largest moon and the only moon in our solar system with an atmosphere. Though Huygens’s lived only a couple of hours on Titan, the dusty orange images it radioed home unveiled a geomorphology that is Earth-like yet utterly alien: pebbles made of water ice, not rock; ridges covered with sticky hydrocarbon tholins, not dirt; and channels carved by rivers of methane, not water. Huygens’s success was particularly sweet because Titan’s thick nitrogen and methane atmosphere had previously thwarted astronomers’ attempts to look at the moon’s surface. The feat is still unmatched as the most ...