Wednesday, November 26, 2014


What does Miranda mean to you? An old girl friend? A planet the Serenity went to in order to uncover a harsh secret in Fire-Fly?

No? How about Uranus’s Frankenstein moon?

Miranda, small, one seventh the size of the Earth’s moon, and the innermost of Uranus’s five moons is also put together; sort of a mess of mismatched piece, or at least the Southern hemisphere. Scientists are only aware of what Miranda's southern hemisphere looks like as thanks to NASA's Voyager 2 spacecraft & its 1986 Uranus flyby but alas it did not image Miranda's northern hemisphere.

But finally due to the much thought and research the strange appearance of Miranda in part may now be explained.

Miranda’s original orbit of Uranus was not so pretty and round but more ecliptic. Three dimensional computer simulations of Miranda’s earlier orbit show the forces pulling and squeezing Miranda. This resulted in the generation of a substantial amount of heat.  

That heat then caused Miranda’s icy mantle to move about vigorously causing Convective heat transfer which is very much like Earth’s mantle of rock does. During this process warm buoyant ice rises to the surface of Miranda and contorts the coronae. (Coronae is an oval shaped feature/often a surface deformation – usually formed via that upwelling of warm material beneath the surface.)

Miranda as strange as she is, is actually quite small. Only 293 miles wide (our moon is ~2000) and this ball of ice & rock has a landscape that is quite unique complete with giant canyons that dwarf the Grand Canyon. Miranda has 3 coronae that are unique in the solar system in that they are shaped crudely, and each is least 120 miles (200 km) wide. The coronae are separate from their more heavily cratered surroundings as here are belts of concentric ridges and troughs. The three coronae — Arden, Elsinore and Inverness — are named after locations in Shakespeare's plays.

For convection to drive Miranda's surface deformation, the substance of the surface must be incredibly weak – weaker than predicted in labs. The same concept, oddly enough, is true of Earth. In order for Earth to have its rocky surface deform as it has, it must have a certain weakness to its surface.

Miranda, a unique name for a unique moon.

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