Rille

As grooves elongated trough- like depressions are referred to the Earth's natural satellite, the Moon, in geology and planetary sciences. On Earth, one would refer to similar formations as ditches or channels, but for the moon, the name Rima ( pl.: Rimae ) has been established. There are three kinds of grooves:

• Elongated grooves caused by geological faults. They are usually several 1000 meters wide and hundreds of kilometers long. Their depth is up to 400 meters.
• Spiral grooves are meandering and let in the formation of lava flows or riverbeds think. There are often crater-like holes at the ends of several 100 km long grooves.
• Curved grooves whose origin is attributed to lava flows. Here the research is still uncertain.

The most famous moon grooves are

• Hyginus the groove with the small crater Hyginus on the break point of the groove
• The branched Triesnecker grooves,
• The Rima Hadley, landed in the vicinity of Apollo 15 at the foot of the Montes Apenninus
• The broad Ariadaeus - groove.

Detail see List of groove structures of the Moon.