EDITED: Farewell, Cassini.
Last night (MST), a NASA spacecraft fell in orbit between the planet Saturn and its rings. It is the first time any human-made object has done so. The spacecraft, called Cassini after the Italian-French astronomer and mathematician Giovanni Domenico Cassini, is in its 271st orbit of Saturn. It entered its first orbit in 2004 as part of the NASA-ESA Cassini-Huygens mission. The Huygens portion of the mission comprised a probe that landed on Saturn's largest moon, Titan. Cassini's "grand finale," which began last night, will take the spacecraft between the rings and the planet on every remaining orbit to study in unprecedented detail the planet's atmosphere and ring structures. Cassini's final maneuver will dive the spacecraft into Saturn's atmosphere on it 293rd orbit in September. Up-to-the-moment mission updates are available here. A gateway to all NASA-JPL mission resources is available here.