noun
- a long narrow valley or trench on the surface of the moon
Usage: astronomy
Examples
- The astronomer studied the rille through her telescope.
- Apollo 15 landed near Hadley Rille on the lunar surface.
- The rille appeared as a dark line cutting across the moon’s bright surface.
- Scientists believe this rille was formed by ancient lava flows.
- The spacecraft photographed several rilles in the lunar highlands.
- Hadley Rille is one of the most famous rilles on the moon.