The observed changeof each signal as Cassini moved behind the rings provided a profile ofthe distribution of ring material as a function of distance fromSaturn, or an optical depth profile.

Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other in a ring, called a gantry.

The train station complex on the China side was an island of noontime naps, surrounded by rice paddies, duck ponds, and the occasional water buffalo.