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Earth
One of the planets in the solar system, the third in distance from the sun and the fifth largest of the planets in diameter. The mean distance of the earth from the sun is 149,503,000 km (92,897,000 mi). It is the only planet known to support life, although some of the other planets have atmospheres and contain water.
The earth is not a perfect sphere but is slightly oblate, or flattened at the poles. The diameter of the earth measured around the North Pole and the South Pole is about 42 km (26 mi) less than the diameter of the earth measured at the equator.
Planet Profile
Mass (kg)............................................5.98
x 10^24
Diameter (km)........................................12756
Mean density (kg/m^3) ...............................5520
Escape velocity (m/sec)..............................11200
Average distance from Sun (AU).......................1
Rotation period (length of day in Earth hours).......23.93
Revolution period (length of year in Earth days).....365.26
Obliquity (tilt of axis in degrees)..................23.4
Orbit inclination (degrees)..........................0
Orbit eccentricity (deviation from circular).........0.017
Mean surface temperature (K).........................281
Maximum surface temperature (K)......................310
Minimum surface temperature (K)......................260
Visual geometric albedo (reflectivity)...............0.39
Highest point on surface.............................Mount
Everest (over 8 km above sea-level)
Atmospheric components...............................78%
nitrogen, 21% oxygen, 1% argon
Surface materials....................................basaltic
and granitic rock and altered materials
You can learn more about the planet Earth by either clicking on one of the subjects below or go to “Planet Earth”.
Courtesy of Kennedy Space Center
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