Ariel
Moon· orbits Uranus
Ariel is the brightest of Uranus's moons, its icy surface cut by a network of fault valleys (chasmata) that suggest past geological activity.
Open in 3D viewSee Ariel in the live, interactive 3D map
Key facts
Mass
1.25 × 10²¹ kg
0.017 Moon masses
Radius
579 km
33% of our Moon's radius
Surface gravity
0.249 m/s²
3% of Earth's
Day length
2.5 days
Orbit around Uranus
2.52 Earth days
Science
Physical
- Mass
- 1.25 × 10²¹ kg · 0.017 Moon masses
- Radius
- 579 km · 33% of our Moon's radius
- Density
- 1,539 kg/m³ · 1.5× water
- Surface gravity
- 0.249 m/s² · 3% of Earth's
- Escape velocity
- 537 m/s · 5% of Earth's
Orbit around Uranus
- Distance from Uranus
- 83,135 km
- Orbital period
- 2.5 days
- Eccentricity
- 0.001
- Inclination
- 0.00 °
Rotation
- Rotation period
- 2.5 days
- Tidal locking
- Tidally locked to its parent
Temperature
- Mean
- 60 K (-213 °C)
Composition
- Bulk composition
- Roughly equal water ice and silicate rock, with possible carbon-dioxide ice.
Radiation & temperature
- Insolation
- 0.00264 S⊕ · 1/378 of the sunlight Earth receives
- Bond albedo
- 0.53 · reflects 53% of incoming sunlight
- Equilibrium temperature
- 52 K (-221 °C)
- Measured mean temperature
- 60 K (-213 °C)
- Greenhouse warming
- +8 K
Discovery & history
- Discovered
- October 24, 1851
- By
- William Lassell
- Method
- Visual discovery (telescopic)
- Name
- Ariel, an airy spirit in Shakespeare's 'The Tempest' and Pope's 'The Rape of the Lock'.
William Lassell discovered Ariel in 1851. The brightest of Uranus's moons, it also has the youngest surface, criss-crossed by fault canyons whose floors appear to have been flooded by icy flows.
Images
Images from open archives · credit shown per image