Mommur Chasma

Mommur Chasma is the largest 'canyon' on the known part of the surface of Uranus' moon Oberon.

[1] This feature probably formed during crustal extension at the early stages of moon's evolution, when the interior of Oberon expanded and its ice crust cracked as a result.

[2] The canyon is an example of graben (rift valley) or scarp produced by normal fault(s).

[3] The Gazetteer of Planetary Nomenclature states that Mommur Chasma is named after the forest home of the fairy king Oberon in A Midsummer Night's Dream.

[1] In fact, Oberon's home is not named in Shakespeare's play; it appears instead in the French epic Huon of Bordeaux.