The material which forms the rings is less than 0.1% the amount
of material in either moon.
| Orbital Elements | ||
| ||
| Mean distance from Sun | 1,429,400,000 km | = 9.5388 astronomical units |
| Perihelion distance | 1,352,550,000 km | = 9.0412 astronomical units |
| Aphelion distance | 1,514,500,000 km | = 10.1238 astronomical units |
| Eccentricity of orbit | 0.0560 | |
| Inclination of orbit | 2.488° | relative to Earth's orbit |
| Period of orbit | 29.458 years | |
| Synodic period | 378 days | relative to Earth |
| Mean orbital speed | 9.67 km/s | |
| Minimum orbital speed | 9.09 km/s | |
| Maximum orbital speed | 10.18 km/s | |
| Physical Properties | ||
| ||
| Mean diameter | 116,464 km | = 9.2 Earth diameters |
| Equatorial radius | 60,268 km | |
| Polar radius | 54,364 km | |
| Oblateness | 1/9 | |
| Mass | 5.688 x 1026 kg | = 95.181 Earth masses |
| Mean density | 0.69 g/cm3 | |
| Rotational period | 10.233 hours | |
| Inclination of axis | 25.33° | relative to the axis of its orbit |
| Gravity at cloud tops | 9.05 m/s2 | |
| Escape speed | 35.5 km/s | from cloud tops |
| Visual geometric albedo | 0.47 | |
| Visual magnitude (Vo) | 0.67 | maximum, as seen from Earth |
| Mean visible cloud temperature | -125°C | |
| Atmospheric pressure | 1.4 bars | at cloud tops |
| Atmospheric Composition | |
| |
| Hydrogen (H2) | 96.3% |
| Helium (He) | 3.25% |
Moons
One large moon, four medium-size moons, and more than two dozen small moons.
To my Space and Science home page
for more about the Solar System
Jeff Root
September 4, 2003