Discovery | |
---|---|
Discovered by | |
Discovery date | July 18, 1999 |
Designations | |
Designation | Uranus XX |
Pronunciation | /ˈstɛfənoʊ/ STEF-ən-oh [1] [2] |
Adjectives | Stephanonian /ˌstɛfəˈnoʊniən/ STEF-ə-NOH-nee-ən [3] |
Orbital characteristics | |
Mean orbit
radius | 8,004,000 km [4] [5] |
Eccentricity | 0.2292 [5] |
677.37 d | |
Inclination | 141.81° (to the ecliptic),144° [4] |
Satellite of | Uranus |
Group | Caliban group |
Physical characteristics | |
Mean radius | 16 km (estimate) [6] |
~3,000 km2 (estimate) | |
Volume | ~20,000 km3 (estimate) |
Mass | ~2.2×1016 kg (estimate) |
Mean
density | ~1.3 g/cm3 (assumed) |
~0.0041 m/s2 (estimate) | |
~0.013 km/s (estimate) | |
? | |
? | |
Albedo | 0.04 (assumed) [6] |
Temperature | ~65 K (estimate) |
Stephano ( /ˈstɛfənoʊ/ STEF-ən-oh) is a retrograde irregular satellite of Uranus. It was discovered by Brett J. Gladman, et al. in 1999, and given the provisional designation S/1999 U 2. [7] [8] [9] [10] [11]
Confirmed as Uranus XX, it was named after the drunken butler in William Shakespeare's play The Tempest in August 2000. [12]
The orbital parameters suggest that it may belong to the same dynamic cluster as Caliban, suggesting common origin. [13]