Uranus' Moons 

ARIEL:
        Ariel is the twelfth of Uranus's known satellites with a diameter of 
1158 km, a mass of 1.27e21 kg, and an orbit that takes it 190,930 km from Uranus.
Discovered by Lassell in 1851, it was named after the mischievous airy spirit in 
Shakespeare's The Tempest. Ariel is Umbriel's twin, but in size only. Ariel does, 
however, appear quite similar to Titania (Titania is 35% larger though). 

       All of Uranus' large moons are a mixture of about 40-50% water ice with 
the rest rock, a somewhat larger fraction of rock than Saturn's large moons such
 as Rhea. Ariel is the lightest of the moons in color. It's surface is one of 
the least cratered, which also means one of the youngest. It resembles Titania 
more than Umbriel. Its surface displays a network of faults and rift valleys. 
On Ariel, volcanoes have resurfaced most of the terrain. The lava that is 
emitted is not molten rock like that of earth. Instead, it is a glacier-like 
mixture of ice and rock, slightly warmer than the surface of Ariel. This material 
may have flowed like a glacier. Water froze and expanded, shattering the crust 
and resulted in valleys. 

       Ariel's surface is a mixture of cratered terrain and systems of 
interconnected valleys hundreds of kilometers long (left, above) and more than 
10 km deep. This is similar to, but much larger and more extensive than the 
situation on Titania. Some of the craters appear to be half-submerged. Ariel's 
surface is clearly relatively young (though older than some such as Enceladus); 
obviously some sort of resurfacing processes have been at work. Some ridges in 
the middle of the valleys are interpreted as upwellings of ice. Ariel may have 
been hot inside long ago, but it's cold now. Perhaps the valleys are cracks that 
formed when Ariel froze. 

BELINDA

       Belinda is the ninth of Uranus' satellites. The orbit is 75,255 km from 
Uranus. Its diameter is 68 km. The name, Belinda, is from Alexander Pope's The 
Rape of the Lock. Voyager 2 discovered the moon, Belinda, in 1986. 

BIANCA

       Bianca is the third of Uranus' satellites. Its orbit is 59,165 km from 
Uranus and has a diameter of 44 km. Its mass is unknown. The name, Bianca, is 
from Shakespeare's Taming of the Shrew. Voyager 2 discovered this moon in 1986.

CORDELIA

       Cordelia is the innermost of Uranus' satellites. Its diameter is 26 km 
long. The name Cordelia is from Shakespeare's King Lear. The Voyager 2 
discovered Cordelia in 1986. The two moons, Cordelia and Ophelia, orbit inside 
the orbit radius.  

CRESSIDA:

       Cressida is the fourth of Uranus' satellites. It has an orbit of 61,767 
km from Uranus. The diameter is 66 km long. The name, Cressida, is the daughter 
of Calchas in Shakespeare's Troilus and Cressida. Voyager 2 discovered this moon
in 1986. 

DESDEMONA:

       Desdemona is the fifth of Uranus' satellites. Its orbit 62,659 km from 
Uranus. The diameter is 58 km. The mass is unknown. The name, Desdemona, is the 
wife of Othello in Shakespeare's Othello. This moon was discovered by Voyager 2 
in 1986.

JULIET:

       Juliet is the sixth of Uranus' satellites. The orbit 64,358 km from 
Uranus. Juliet's diameter is 84 km. The mass of this moon is unknown. The name 
Juliet is from Shakespeare's Romeo and Juliet. Juliet, the moon, was discovered 
by Voyager 2 in 1986. 

MIRANDA:

        Miranda is not one of the larger satellites of Uranus; however, it was 
the one that was approached the closest by Voyager 2. This was not the satellite
scientists would have chosen to get close to if they had a choice, but they had 
no choice. Voyager 2 had to fly close to the planet in order to get the boost it
needed to go to Neptune. The resolution at which the larger satellites were 
photographed was around 2 to 3 kilometers (1.2 to 1.9 miles). On the other hand,
details on the order of a few hundred meters can be seen on Miranda. Fortunately, 
Miranda turned out to be the most remarkable of all the satellites. Miranda is a 
small satellite with a diameter of 470 kilometers (290 miles). Its surface is 
unlike anything in the solar system with features that are jumbled together in 
a haphazard fashion. Miranda consists of huge fault canyons as deep as 20 kilometers 
(12 miles), terraced layers and a mixture of old and young surfaces. The younger 
regions might have been produced by incomplete differentiation of the moon, a 
process in which upwelling of lighter material surfaced in limited areas. 
Alternatively, scientists believe that Miranda may have been shattered as many 
as five times during its evolution. After each shattering the moon would have 
reassembled from the remains of its former self with portions of the core 
exposed and portions of the surface buried. Miranda's appearance can be 
explained by theories, but the real reason is still unknown. Given Miranda's 
small size and low temperature (-187° C or -335° F), the degree and diversity 
of the tectonic activity on this moon have surprised scientists. It is believed 
that an additional heat source such as tidal heating caused by the gravitational 
tug of Uranus must have been involved. In addition, some means must have mobilized 
the flow of icy material at low temperatures. Miranda was named after the 
daughter of the magician Prospero in Shakespeare's play The Tempest. Miranda 
was discovered in 1948. It has a mass of 6.33e+19 kg and an equatorial radius 
of 235.8 km. Miranda is 129,780 km away from Uranus. 

OBERON:

        Oberon is the outermost moon of Uranus and the second largest. Its 
diameter is 1523 km. It has craters of all sizes, some over 60 miles in diameter. 
In comparison to other moos, Oberon is rather evenly cratered. It is the twin of 
Titania-almost identical in size, density, color, and reflectivity.

       Here's an interesting fact, the names Oberon and Titania were chosen 
together because Oberon is the King of the Fairies and husband of Titania in 
Shakespeare's Midsummer-Night's Dream. Oberon and another moon, Umbriel, appear 
to be similar as well. Oberon is 35% larger. Oberon has many large faults. This 
is indicative of geologic activity in Oberon's past history.

OPHELIA:

       Ophelia is the second of Uranus' satellites. Its diameter is 32 km in 
length. Its mass is unknown. The name, Ophelia, is from Shakespeare's Hamlet. 
Ophelia is the daughter of Polonius in Shakespeare's Hamlet. The moon, Ophelia, 
was discovered by the Voyager 2 in 1986. Ophelia seems to be the outer satellite
for Epsilon Ring of Uranus.

PORTIA:

       Portia is the seventh of Uranus' moons. Its orbit is 66,097 km from 
Uranus. The diameter is 110 km. The name, Portia, is from Shakespeare's 
Merchant of Venice. The moon, Portia, was discovered by Voyager 2 in 1986.

PUCK:

       Puck is the tenth of Uranus' satellites. Its orbit is 86,006 km from 
Uranus. Its diameter 154 km. The name Puck is from Shakespeare's Midsummer-Night's 
Dream. It was discovered by the Voyager 2 in 1986. Puck and the other small 
moons are very dark.

ROSALIND:

       Rosalind is the eighth of Uranus' satellites. Its orbit is 69,927 km 
from Uranus. The diameter is 54 km. The name, Rosalind, is from Shakespeare's 
As You Like It. The moon, Rosalind, was discovered by Voyager 2 in 1986.

TITANIA:

        Titania is the fourteenth and largest of Uranus' moons. It is the twin 
moon of Oberon. It is named after the wife of a character, Oberon, in Shakespeare's, 
Midsummer Night's Dream. Its almost the same as Oberon in size, density, color, 
and even reflectivity. Titania's diameter is 1578 km long. The terrain of 
Titania is crisscrossed by cracks, ranging some 1,000 miles long, 30 miles 
across, and as much as 3 miles deep. It is about half rock and half ice. The 
surface temperature of the satellite is -315 degrees Fahrenheit.

       Titania's surface is a combination of craters and networks of interconnected 
valleys that are hundreds of kilometers long. Some of these craters seem to be 
partially submerged. 

       One theory about this moon's history is that it may once have been hot 
enough to be a liquid. The surface probably cooled first; and when the interior 
froze it expanded forcing the surface to crack and resulted in the formation of 
the valleys. 

UMBRIEL:

        Umbriel is one of Uranus' more bland moons. It is the darkest of the 
moons and shows little variation in color. It has no craters with bright rays 
like Oberon. There are two bright features visible. One is on the slope of the 
central peak of a crater. The second is a ring that is 50 miles in diameter. 
Umbriel has a diameter of 740 miles and is smaller than Oberon and Titania. It 
can be that the dark regions are made of carbon-rich with colored ice.