Ariel
Uranus I
Ariel Facts
- Ariel is the twelfth of Uranus's known satellites:
- distance from Uranus: 190,930 km
- diameter: 1158 km
- mass: 1.27e21 kg
- Pronounced "AIR ee el"
- Ariel is a mischievous airy spirit in Shakespeare's The Tempest.
- Discovered by Lassell in 1851.
- Ariel and Titania appear quite similar though Titania
is 35% larger. All of Uranus's 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's surface is a mixture of cratered terrain and systems
of interconnected
valleys hundreds of kilometers long (picture 1, 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 which formed when Ariel froze.
Pictures
- (above) Ariel craters
103k gif;
52k jpg;
295k gif
Ariel
196k gif
Ariel mosaic
57k gif;
187k jpg
More about Ariel
Open Issues
- What caused the deep valleys and the resurfacing?
... Uranus
... Miranda
... Ariel
... Umbriel
... 
Bill Arnett; last updated:
1995 March 3
