What are the current accepted theories of the formation of the Uranian moon Miranda? Miranda, a moon of Uranus is unique in that it has a very fractured surface



Source: University of Oregon

The surface is said to be jagged and fractured, with comparatively large disjointed cliffs and great faultlines.

What are the current accepted theories for the formation of such a strange world?

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As Miranda is a rather small object (only 235km diameter) it may simply have not enough mass to make it matter settle into hydrostatic equilibrium under the influence of its gravity, thus it basically retains the irregular shape most asteroids have. This nice arxiv paper discusses the mass limits necessary for a stellar body to settle into a nice round shape:

http://arxiv.org/ftp/arxiv/papers/1004/1004.1091.pdf