Crater diameters range from 40 km to small pit-like features less than 1 mm in diameter Since Krella has no atmosphere, the landscape is stark with the only erosion due to thermal stress and particle impact. A layer of meteoritic dust covets the surface of KreKn to a depth of 11 cm. Krelln orbits Arrakisonce every 25.5 days with nearly the same face toward Arrakis. Libration of 16 degrees occurs once each oibit. Because of the small angular diameter of Krelln (10 36 arc minutes), total eclipses of Canopus do not occur Krelln has been of limited commercial use; however, ritanite mining operations were established Krelln has also functioned as an observational facility for deep space surveillance Arvon-secottd satellite. Arvon is the smaller of the Arrakian satellites with a radius of 201 km. The satellite orbits Arrakis in 5 7 days and occupies a nearly circular orbit with a perigee distance of 103,000km Arvon orbits Arrakis in less man one-fourth the time required for JCrelte.