5th Largest Moon of Uranus - Miranda (14th Moon outwards from Uranus)

Miranda is the fifth largest of the Uranus moons, and the 18th largest moon in the Solar System.

Miranda is one of the few bodies in the Solar System in which the equatorial circumference is shorter than the pole-to-pole circumference.

Discovery

Miranda was discovered in telescopic photos of the Uranian system by Gerard P. Kuiper on February 16, 1948 at McDonald Observatory.

Naming

Miranda the moon was named after Miranda from William Shakespeare's play The Tempest by Kuiper in his report of the discovery.

Stats

Diameter: 472 km

Semi-major axis: 129,320 km

Orbital Period: 1.41 days

Formation

Miranda looks like it was pieced together from parts that didn't quite merge properly. At 472 km in diameter, it's only one-seventh as large as Earth's moon, a size that seems unlikely to support much tectonic activity. Yet Miranda sports one of the strangest and most varied landscapes among extraterrestrial bodies.

Scientists disagree about what processes are responsible for Miranda's features. One possibility is that the moon may have been smashed apart in some colossal collision, and the pieces then haphazardly reassembled.

Another, perhaps more likely, scenario is that the coronae are sites of large rocky or metallic meteorite strikes which partially melted the icy subsurface and resulted in episodic periods of slushy water rising to Miranda's surface and refreezing.

Orbit

Miranda takes as long to rotate on its axis as it does to make one orbit of Uranus; and therefore always keeps the same hemisphere pointed to Uranus.

Physical characteristics

Miranda's surface may be mostly water ice, with the low-density body also probably containing silicate rock and organic compounds in its interior.

Miranda's surface has patchwork regions of broken terrain indicating intense geological activity in the moon's past, and is criss-crossed by huge canyons.

Exploration Status

So far the only close-up images of Miranda have been from the Voyager 2 probe, which photographed the moon during its flyby of Uranus in January 1986.

No other spacecraft has ever visited the Uranian system or Miranda, and no mission is planned in the foreseeable future.