Rille Trivia Questions

It's borrowed from German 'Rille' meaning groove. Astronomers adopted the term in the 19th century for these lunar features.

The Vallis Schröteri rille is about 160 miles long, while the Grand Canyon is 277 miles—but many lunar rilles, like the sinuous ones, exceed 100 miles easily.

Most lunar rilles are actually collapsed lava tubes or channels formed by flowing lava, not water. The moon had no significant liquid water rivers.

Sinuous rilles meander like rivers, winding across the lunar surface. Only arcuate rilles are curved, but many are indeed winding.

The first detailed observations of rilles came in the mid-19th century, particularly by Johann Schröter in the 1790s. 1600s telescopes were too crude.

Vallis Schröteri is about 160 miles, but the Rima Hadley is shorter. However, some sinuous rilles can exceed 300 miles, like Vallis Snellius.

Rilles have been observed on Mars, Venus, and even on some asteroids. They're not unique to Earth's moon.

Apollo 15 landed near Hadley Rille and astronauts David Scott and James Irwin collected green volcanic glass beads from the area.