Kachina Chasmata

The faults bound down-dropped crustal blocks forming structures called graben.

[2] The canyons cut the cratered terrain, which means that they were formed at a relatively late stage of the moon's evolution, when the interior of Ariel expanded and its ice crust cracked as a result.

[3] During the Voyager 2 flyby in 1986 the northern hemisphere of Ariel was not illuminated by the Sun because the spacecraft arrived during a southern solstice on Uranus.

Nevertheless, because it was still illuminated by light reflected from Uranus, scientists using advanced processing methods were able to detect some details in the dark hemisphere.

These analyses revealed a continuation of the Kachina Chasmata into the dark hemisphere, possibly as far as to the opposite limb.