mirrored file at http://SaturnianCosmology.Org/ For complete access to all the files of this collection see http://SaturnianCosmology.org/search.php ========================================================== ___________________________________ Saturn Fact Sheet ___________________________________ [1][Voyager 2 image of Saturn] _________________________________________________________________ Saturn/Earth Comparison _________________________________________________________________ Bulk parameters Saturn Earth Ratio (Saturn/Earth) Mass (10^24 kg) 568.46 5.9736 95.159 Volume (10^10 km^3) 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/m^3) 687 5,515 0.125 Gravity (eq., 1 bar) (m/s^2) 10.44 9.80 1.065 Acceleration (eq., 1 bar) (m/s^2) 8.96 9.78 0.916 Escape velocity (km/s) 35.5 11.19 3.172 GM (x 10^6 km^3/s^2) 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/m^2) 14.90 1,367.6 0.011 Black-body temperature (K) 81.1 254.3 0.319 Moment of inertia (I/MR^2) 0.210 0.3308 0.635 J[2] (x 10^-6) 16,298. 1082.63 15.054 Number of natural satellites 31 1 Planetary ring system Yes No _________________________________________________________________ Orbital parameters Saturn Earth Ratio (Saturn/Earth) Semimajor axis (10^6 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 (10^6 km) 1,352.55 147.09 9.195 Aphelion (10^6 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 _________________________________________________________________ Saturn Observational Parameters Discoverer: Unknown Discovery Date: Prehistoric Distance from Earth Minimum (10^6 km) 1195.5 Maximum (10^6 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 (10^6 km) 1277.42 Apparent diameter (seconds of arc) 19.5 Apparent visual magnitude 0.7 Maximum apparent visual magnitude 0.43 Saturn Mean Orbital Elements (J2000) 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 _________________________________________________________________ North Pole of Rotation 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 _________________________________________________________________ Saturnian Magnetosphere Dipole field strength: 0.210 gauss-Rs^3 Dipole tilt to rotational axis: < 1 degree Dipole offset (planet center to dipole center) distance: 0.04 to 0.05 Rs northw ard 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 _________________________________________________________________ Saturnian Atmosphere 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/m^3 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 (H[2]) - 96.3% (2.4%); Helium (He) - 3.25% (2.4%) Minor (ppm): Methane (CH[4]) - 4500 (2000); Ammonia (NH[3]) - 125 (75); Hydrogen Deuteride (HD) - 110 (58); Ethane (C[2]H[6]) - 7 (1.5 ) Aerosols: Ammonia ice, water ice, ammonia hydrosulfide _________________________________________________________________ If no sub- or superscripts appear on this page - for example, if the "Mass" is given in units of "(1024 kg)" - you may want to check the [2]notes on the sub- and superscripts. [3]bullet Notes on the factsheets - definitions of parameters, units, notes on sub- and superscripts, etc. _________________________________________________________________ [4]bullet Saturnian Satellite Fact Sheet [5]bullet Saturnian Rings Fact Sheet [6]bullet Planetary Fact Table - metric units [7]bullet Planetary Fact Table - U.S. units [8]bullet Planetary Fact Table - Earth ratio [9]bullet Saturn Home Page [10]bullet Directory to other Planetary Fact Sheets [11]bullet NSSDC Planetary Home Page _________________________________________________________________ Questions and comments about this page should be addressed to: Dr. David R. Williams, [12]dwilliam at nssdc.gsfc.nasa.gov, +1-301-286-1258 NSSDC, Mail Code 633, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 or Dr. Edwin V. Bell II, [13]ed.bell at gsfc.nasa.gov, +1-301-286-1187 NSSDC, Mail Code 633, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 [NSSDC logo] _________________________________________________________________ NASA Official: Ed Grayzeck, edwin.j.grayzeck at nasa.gov Last Updated: 19 May 2004, DRW References Visible links 1. http://nssdc.gsfc.nasa.gov/planetary/image/saturn_voy2.jpg 2. http://nssdc.gsfc.nasa.gov/planetary/factsheet/fact_notes.html 3. http://nssdc.gsfc.nasa.gov/planetary/factsheet/fact_notes.html 4. http://nssdc.gsfc.nasa.gov/planetary/factsheet/saturniansatfact.html 5. http://nssdc.gsfc.nasa.gov/planetary/factsheet/satringfact.html 6. http://nssdc.gsfc.nasa.gov/planetary/factsheet/index.html 7. http://nssdc.gsfc.nasa.gov/planetary/factsheet/planet_table_british.html 8. http://nssdc.gsfc.nasa.gov/planetary/factsheet/planet_table_ratio.html 9. http://nssdc.gsfc.nasa.gov/planetary/planets/saturnpage.html 10. http://nssdc.gsfc.nasa.gov/planetary/planetfact.html 11. http://nssdc.gsfc.nasa.gov/planetary/planetary_home.html 12. mailto:dwilliam at nssdc.gsfc.nasa.gov 13. mailto:ed.bell at gsfc.nasa.gov Hidden links: 14. http://nssdc.gsfc.nasa.gov/planetary/planets/saturnpage.html