| Uranus |
Earth |
Ratio (Uranus/Earth) |
|
|---|---|---|---|
| Mass (1024 kg) | 86.811 | 5.9722 | 14.54 |
| Volume (1010 km3) | 6,833 | 108.321 | 63.08 |
| Equatorial radius (1 bar level) (km) | 25,559 | 6,378.1 | 4.007 |
| Polar radius (1 bar level) (km) | 24,973 | 6,356.8 | 3.929 |
| Volumetric mean radius (km) | 25,362 | 6,371.0 | 3.981 |
| Ellipticity (Flattening) | 0.02293 | 0.00335 | 6.84 |
| Mean density (kg/m3) | 1,270 | 5,513 | 0.230 |
| Gravity (mean, 1 bar) (m/s2) | 9.01 | 9.82 | 0.918 |
| Acceleration (eq., 1 bar) (m/s2) | 8.69 | 9.78 | 0.889 |
| Acceleration (pole, 1 bar) (m/s2) | 9.19 | 9.83 | 0.935 |
| Escape velocity (km/s) | 21.3 | 11.19 | 1.903 |
| GM (x 106 km3/s2) | 5.7940 | 0.39860 | 14.54 |
| Bond albedo | 0.300 | 0.294 | 1.020 |
| Geometric albedo | 0.488 | 0.434 | 1.12 |
| V-band magnitude V(1,0) | -7.11 | -3.99 | - |
| Solar irradiance (W/m2) | 3.69 | 1,361.0 | 0.0027 |
| Black-body temperature (K) | 58.1 | 254.0 | 0.229 |
| Moment of inertia (I/MR2) | 0.225 | 0.3308 | 0.680 |
| J2 (x 10-6) | 3343.43 | 1082.63 | 3.088 |
| Number of natural satellites | 28 | 1 | |
| Planetary ring system | Yes | No |
| Uranus |
Earth |
Ratio (Uranus/Earth) |
|
|---|---|---|---|
| Semimajor axis (106 km) | 2,867.043 | 149.598 | 19.165 |
| Sidereal orbit period (days) | 30,685.400 | 365.256 | 84.011 |
| Tropical orbit period (days) | 30,588.740 | 365.242 | 83.749 |
| Perihelion (106 km) | 2,732.696 | 147.095 | 18.578 |
| Aphelion (106 km) | 3,001.390 | 152.100 | 19.733 |
| Synodic period (days) | 369.66 | - | - |
| Mean orbital velocity (km/s) | 6.79 | 29.78 | 0.228 |
| Max. orbital velocity (km/s) | 7.13 | 30.29 | 0.235 |
| Min. orbital velocity (km/s) | 6.49 | 29.29 | 0.222 |
| Orbit inclination (deg) | 0.770 | 0.000 | - |
| Orbit eccentricity | 0.0469 | 0.0167 | 2.808 |
| Sidereal rotation period (hrs) | -17.24* | 23.9345 | 0.720 |
| Length of day (hrs) | 17.24 | 24.0000 | 0.718 |
| Obliquity to orbit (deg) | 97.77 | 23.44 | - |
| Inclination of equator (deg) | 82.23 | 23.44 | 3.508 |
Discoverer: William Herschel
Discovery Date: 13 March 1781
Distance from Earth
Minimum (106 km) 2580.6
Maximum (106 km) 3153.5
Apparent diameter from Earth
Maximum (seconds of arc) 4.1
Minimum (seconds of arc) 3.3
Mean values at opposition from Earth
Distance from Earth (106 km) 2721.37
Apparent diameter (seconds of arc) 3.8
Apparent visual magnitude 5.57
Maximum apparent visual magnitude 5.38
Semimajor axis (AU) 19.19126393 Orbital eccentricity 0.04716771 Orbital inclination (deg) 0.76986 Longitude of ascending node (deg) 74.22988 Longitude of perihelion (deg) 170.96424 Mean Longitude (deg) 313.23218
Right Ascension: 257.311 Declination : -15.175 Reference Date : 12:00 UT 1 Jan 2000 (JD 2451545.0)
Dipole field strength: 0.228 Gauss-Ru3
Dipole tilt to rotational axis: 58.6 degrees
Longitude of tilt: 53.6 degrees
Dipole offset: 0.352 Ru
Surface (1 Ru) field strength: ~0.1 - 1.0 Gauss
Ru denotes Uranian model radius, here defined to be 25,600 km
Surface Pressure: >>1000 bars Temperature at 1 bar: 76 K (-197 C) Temperature at 0.1 bar: 53 K (-220 C) Density at 1 bar: 0.42 kg/m3 Wind speeds: 0-250 m/s Scale height: 27.7 km Mean molecular weight: 2.64 Atmospheric composition (by volume, uncertainty in parentheses) Major: Molecular hydrogen (H2) - 82.5% (3.3%); Helium (He) - 15.2% (3.3%) Methane (CH4) - 2.3% Minor (ppm): Hydrogen Deuteride (HD) - 148 Aerosols: Ammonia ice, water ice, ammonia hydrosulfide, methane ice(?)
Uranian Satellite Fact Sheet
Uranian Rings Fact Sheet
Planetary Fact Table
- metric units
Planetary Fact Table
- U.S. units
Planetary Fact Table
- Earth ratio
Uranus Home Page
Directory to other Planetary Fact Sheets
Notes on the factsheets
- definitions of parameters, units, notes on sub- and superscripts, etc.
Author/Curator: