Earth

This article is about the planet. For other uses, see Earth (disambiguation).

Earth  

"The Blue Marble" photograph of Earth,
taken from Apollo 17
Designations
Alternative names Terra
Orbital characteristics
Epoch J2000.0[note 1]
Aphelion 152,098,232 km
1.01671388 AU[note 2]
Perihelion 147,098,290 km
0.98329134 AU[note 2]
Semi-major axis 149,598,261 km
1.00000261 AU[1]
Eccentricity 0.01671123[1]
Orbital period 365.256363004 days[2]
1.000017421 yr
Average orbital speed 29.78 km/s[3]
107,200 km/h
Mean anomaly 357.51716°[3]
Inclination 7.155° to Sun's equator
1.57869°[4] to invariable plane
Longitude of ascending node 348.73936°[3][note 3]
Argument of perihelion 114.20783°[3][note 4]
Satellites 1 natural (the Moon)
8,300+ artificial (as of 1 March 2001)[5]
Physical characteristics
Mean radius 6,371.0 km[6]
Equatorial radius 6,378.1 km[7][8]
Polar radius 6,356.8 km[9]
Flattening 0.0033528[10]
Circumference 40,075.017 km (equatorial)[8]
40,007.86 km (meridional)[11]
Surface area 510,072,000 km2[12][13][note 5]
148,940,000 km2 land (29.2 %)
361,132,000 km2 water (70.8 %)
Volume 1.08321×1012 km3[3]
Mass 5.9736×1024 kg[3]
Mean density 5.515 g/cm3[3]
Equatorial surface gravity 9.780327 m/s2[14]
0.99732 g
Escape velocity 11.186 km/s[3]
Sidereal rotation
period 0.99726968 d[15]
23h 56m 4.100s
Equatorial rotation velocity 1,674.4 km/h (465.1 m/s)[16]
Axial tilt 23°26'21".4119[2]
Albedo 0.367 (geometric)[3]
0.306 (Bond)[3]
Surface temp.
  Kelvin
  Celsius
min mean max
184 K[17] 287.2 K[18] 331 K[19]
−89.2 °C 14 °C 57.8 °C
Atmosphere
Surface pressure 101.325 kPa (MSL)
Composition 78.08% nitrogen (N2)[3]
20.95% oxygen (O2)
0.93% argon
0.038% carbon dioxide
About 1% water vapor (varies with climate)
Earth (or the Earth) is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets. It is sometimes... [continues]

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