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Earth

From Wikipedia, the free encyclopedia

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

Earth Astronomical symbol of Earth

"The Blue Marble" photograph of Earth, taken by the Apollo 17 lunar mission. The Arabian peninsula, Africa and Madagascar lie in the upper half of the disc, whereas Antarctica is at the bottom.

"The Blue Marble" photograph of Earth, taken during the Apollo 17 lunar mission in 1972

Orbital characteristics

Epoch J2000[n 1]

Aphelion

152,100,000 km (94,500,000 mi)

(1.01673 AU) [n 2]

Perihelion

147,095,000 km (91,401,000 mi)

(0.9832687 AU) [n 2]

Semi-major axis

149,598,023 km (92,955,902 mi)

(1.000001018 AU) [1]

Eccentricity 0.0167086[1]

Orbital period

365.256363004 d [2]

(1.00001742096 yr)

Average orbital speed

29.78 km/s (18.50 mi/s)[3]

(107,200 km/h (66,600 mph))

Mean anomaly

358.617°

Inclination

7.155° to the Sun's equator;

1.57869°[4] to invariable plane;

0.00005° to J2000 ecliptic

Longitude of ascending node

−11.26064°[3] to J2000 ecliptic

Argument of perihelion

114.20783°[3]

Satellites

One natural satellite;

1305 operational artificial satellites[5][n 3]

Physical characteristics

Mean radius

6,371.0 km (3,958.8 mi)[6]

Equatorial radius

6,378.1 km (3,963.2 mi)[7][8]

Polar radius

6,356.8 km (3,949.9 mi)[9]

Flattening 0.0033528[10]

1/298.257222101 (ETRS89)

Circumference

40,075.017 km (24,901.461 mi) (equatorial) [8]

40,007.86 km (24,859.73 mi) (meridional) [11][12]

Surface area

510,072,000 km2 (196,940,000 sq mi)[13][14][n 4]

(148,940,000 km2 (57,510,000 sq mi) (29.2%) land

361,132,000 km2 (139,434,000 sq mi) (70.8%) water)

Volume 1.08321×1012 km3 (2.59876×1011 cu mi)[3]

Mass 5.97237×1024 kg (1.31668×1025 lb)[15]

(3.0×10−6 M☉)

Mean density

5.514 g/cm3 (0.1992 lb/cu in)[3]

Surface gravity

9.807 m/s2 (32.18 ft/s2)[16]

(1 g)

Moment of inertia...