On the final flyby of Cassini's original four-year tour, its radar mapper captured these unusual channels on Titan at the edge of Xanadu, the widest seen in this area.

On the final flyby of Cassini's original four-year tour, its radar mapper captured these unusual channels on Titan at the edge of Xanadu, the widest seen in this area.

Radio Science Front and Center

After a 95-day hiatus since its previous visit, Cassini completed a successful flyby of Titan on Nov. 3, passing the smog-enshrouded moon at an altitude of 1,105 kilometers (687 miles).

During this flyby the Radio Science Subsystem performed critical atmospheric occultations -- watching Earth slip behind Titan and using Cassini's signal to probe the moon's atmosphere. A second Radio Science experiment sent a signal toward Titan's surface which then bounced toward Earth, carrying with it information about the composition and physical state of the surface at low latitudes.