Earth Fact Sheet

Bulk parameters

Mass (1024 kg)                 5.9736
Volume (1010 km3)             108.321
Equatorial radius (km)	        6378
Polar radius (km)               6356
Volumetric mean radius (km)     6371
Core radius (km)                3485
Ellipticity                    0.0034
Mean density (kg/m3)            5520
Surface gravity (m/s2)          9.78
Escape velocity (km/s)         11.186
GM (x 106 km3/s2)               0.3986
Bond albedo                     0.385
Visual geometric albedo         0.367
Visual magnitude V(1,0)        -3.86
Solar irradiance (W/m2)         1380
Black-body temperature (K)       247.3
Topographic range (km)            20
Moment of inertia (I/MR2)       0.3308
J2 (x 10-6)                    1082.63      

Orbital parameters

Semimajor axis (106 km)         149.6
Sidereal orbit period (days)    365.256
Tropical orbit period (days)    365.242
Perihelion (106 km)             147.1
Aphelion (106 km)               152.1
Mean orbital velocity (km/s)     29.79
Orbit inclination (deg)           0.00
Orbit eccentricity                0.0167
Sidereal rotation period (hrs)   23.9345
Obliquity to orbit (deg)         23.45     

Earth Mean Orbital Elements (J2000)

Semimajor axis (AU)                  1.00000011
Orbital eccentricity                 0.01671022
Orbital inclination (deg)            0.00005
Longitude of ascending node (deg)  -11.26064
Longitude of perihelion (deg)      102.94719
Mean Longitude (deg)               100.46435

Terrestrial Magnetosphere

    Dipole field strength: 0.3076 gauss-Re3
    Latitude/Longitude of dipole N: 78.6 degrees N/70.1 degrees W
    Dipole offset (planet center to dipole center) distance: 0.0725 Re
    Latitude/Longitude of offset vector: 18.3 degrees N/147.8 degrees E

Note: Re denotes Earth radii, 6,378 km

Terrestrial Atmosphere

Surface Pressure: 1014 mb
Surface Density: 1.217 kg/m3
Scale height: 8.5 km
Average temperature:  288 K
Diurnal temperature range: 283 K to 293 K
Wind speeds: 0 to 100 m/s
Mean molecular weight: 28.97 g/mole
Atmospheric composition (by volume, dry air):
    Major      : 78.084% Nitrogen (N2), 20.946% Oxygen (O2),
    Minor (ppm): Argon (Ar) - 9340; Carbon Dioxide (CO2) - 350
                 Neon (Ne) - 18.18; Helium (He) - 5.24; CH4 - 1.7
                 Krypton (Kr) - 1.14; Hydrogen (H2) - 0.55
    Water is highly variable, typically makes up about 1%

The Moon

For information on the Moon, see the Moon Fact Sheet