MATHEMATICS OF EARTH
Earth Fact Sheet Our Earth is the only planet known to have life supporting environment and is the third planet from the sun. The Earth has only one natural satellite i.e. our Moon. An Earth year is about 365.26 days long. 71% of the Earth surface is covered with water and the land constitute only 29% of the Earth surface. Bulk parameters Mass (10 24 kg) 5.9723 Volume (10 10 km 3 ) 108.321 Equatorial radius (km) 6378.137 Polar radius (km) 6356.752 Volumetric mean radius (km) 6371.008 Core radius (km) 3485 Ellipticity (Flattening) 0.00335 Mean density (kg/m 3 ) 5514 Surface gravity (m/s 2 ) 9.798 Surface acceleration (m/s 2 ) 9.780 Escape velocity (km/s) 11.186 GM (x 10 6 km 3 /s 2 ) 0.39860 Bond albedo 0.306 Geometric albedo 0.434 V-band magnitude