Saturn Earth Ratio (Saturn/Earth) Mass (1024 kg) 568.46 5.9736 95.159 Volume (1010 km3) 82,713 108.321 763.59 Radius (1 bar level) (km) Equatorial 60,268 6,378.1 9.449 Polar 54,364 6,356.8 8.552 Volumetric mean radius (km) 58,232 6,371.0 9.140 Ellipticity (Flattening) 0.09796 0.00335 29.24 Mean density (kg/m3) 687 5,515 0.125 Gravity (eq., 1 bar) (m/s2) 10.44 9.80 1.065 Acceleration (eq., 1 bar) (m/s2) 8.96 9.78 0.916 Escape velocity (km/s) 35.5 11.19 3.172 GM (x 106 km3/s2) 37.931 0.3986 95.16 Bond albedo 0.342 0.306 1.12 Visual geometric albedo 0.47 0.367 1.28 Visual magnitude V(1,0) -8.88 -3.86 - Solar irradiance (W/m2) 14.90 1,367.6 0.011 Black-body temperature (K) 81.1 254.3 0.319 Moment of inertia (I/MR2) 0.210 0.3308 0.635 J2 (x 10-6) 16,298. 1082.63 15.054 Number of natural satellites 60 1 Planetary ring system Yes No
Saturn Earth Ratio (Saturn/Earth) Semimajor axis (106 km) 1,433.53 149.60 9.582 Sidereal orbit period (days) 10,759.22 365.256 29.457 Tropical orbit period (days) 10,746.94 365.242 29.424 Perihelion (106 km) 1,352.55 147.09 9.195 Aphelion (106 km) 1,514.50 152.10 9.957 Synodic period (days) 378.09 - - Mean orbital velocity (km/s) 9.69 29.78 0.325 Max. orbital velocity (km/s) 10.18 30.29 0.336 Min. orbital velocity (km/s) 9.09 29.29 0.310 Orbit inclination (deg) 2.485 0.000 - Orbit eccentricity 0.0565 0.0167 3.383 Sidereal rotation period (hours) 10.656* 23.9345 0.445 Length of day (hrs) 10.656 24.0000 0.444 Obliquity to orbit (deg) 26.73 23.45 1.140
* Saturnian System III coordinates
Discoverer: Unknown Discovery Date: Prehistoric Distance from Earth Minimum (106 km) 1195.5 Maximum (106 km) 1658.5 Apparent diameter from Earth Maximum (seconds of arc) 20.1 Minimum (seconds of arc) 14.5 Mean values at opposition from Earth Distance from Earth (106 km) 1277.42 Apparent diameter (seconds of arc) 19.5 Apparent visual magnitude 0.7 Maximum apparent visual magnitude 0.43
Semimajor axis (AU) 9.53707032 Orbital eccentricity 0.05415060 Orbital inclination (deg) 2.48446 Longitude of ascending node (deg) 113.71504 Longitude of perihelion (deg) 92.43194 Mean Longitude (deg) 49.94432
Right Ascension: 40.5954 - 0.0577T Declination : 83.5380 - 0.0066T Reference Date : 12:00 UT 1 Jan 2000 (JD 2451545.0) T = Julian centuries from reference date
Dipole field strength: 0.210 gauss-Rs3 Dipole tilt to rotational axis: < 1 degree Dipole offset (planet center to dipole center) distance: 0.04 to 0.05 Rs northward
Note: Saturn's magnetic field has significant quadrapole and octapole moments,
making approximation of the central field as an offset dipole difficult.
Rs denotes Saturnian radii, 60,330 km
Surface Pressure: >>1000 bars Temperature at 1 bar: 134 K (-139 C) Temperature at 0.1 bar: 84 K (-189 C) Density at 1 bar: 0.19 kg/m3 Wind speeds Up to 400 m/s (<30 degrees latitude) Up to 150 m/s (>30 degrees latitude) Scale height: 59.5 km Mean molecular weight: 2.07 g/mole Atmospheric composition (by volume, uncertainty in parentheses) Major: Molecular hydrogen (H2) - 96.3% (2.4%); Helium (He) - 3.25% (2.4%) Minor (ppm): Methane (CH4) - 4500 (2000); Ammonia (NH3) - 125 (75); Hydrogen Deuteride (HD) - 110 (58); Ethane (C2H6) - 7 (1.5) Aerosols: Ammonia ice, water ice, ammonia hydrosulfide
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