Rille

Rimae on the floor of the lunar crater Gassendi, from Apollo 16.
Mamers Valles rille on Mars.
Rima Ariadaeus is categorized as a straight rille (graben) and is over 300 km in length.
Hadley Rille at center is a sinuous rille visited by the Apollo 15 mission.
Detail of part of Hadley Rille

Rille /ˈrɪl/[1] (German for 'groove') is typically used to describe any of the long, narrow depressions in the surface of the Moon that resemble channels. The Latin term is rima, plural rimae. Typically, a rille can be several kilometers wide and hundreds of kilometers in length. However, the term has also been used loosely to describe similar structures on a number of planets in the Solar System, including Mars, Venus, and on a number of moons. All bear a structural resemblance to each other.

  1. ^ "rille". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)