User:FreshYoMama/TWA/Earth/2
Third planet from the Sun / From Wikipedia, the free encyclopedia
Earth is the third planet from the Sun and the only place known in the universe where life has originated and found habitability. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. Approximately 70.8% of Earth's surface is made up of the ocean, dwarfing Earth's polar ice, lakes, and rivers. The remaining 29.2% of Earth's surface is land, consisting of continents and islands. Earth's surface layer is formed of several slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth's liquid outer core generates the magnetic field that shapes the magnetosphere of Earth, deflecting destructive solar winds.
Designations | |||||||||||||
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Gaia, Terra, Tellus, the world, the globe | |||||||||||||
Adjectives | Earthly, terrestrial, terran, tellurian | ||||||||||||
Symbol | |||||||||||||
Orbital characteristics | |||||||||||||
Epoch J2000[n 1] | |||||||||||||
Aphelion | 152,097,597 kilometres (94,509,065 mi) | ||||||||||||
Perihelion | 147098450 km (91402740 mi)[n 2] | ||||||||||||
149598023 km (92955902 mi)[3] | |||||||||||||
Eccentricity | 0.0167086[3] | ||||||||||||
365.256363004 d[4] (1.00001742096 aj) | |||||||||||||
Average orbital speed | 29.7827 km/s[5] (107218 km/h; 66622 mph) | ||||||||||||
358.617° | |||||||||||||
Inclination |
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−11.26064°[5] to J2000 ecliptic | |||||||||||||
2023-Jan-04[7] | |||||||||||||
114.20783°[5] | |||||||||||||
Satellites |
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Physical characteristics | |||||||||||||
Mean radius | 6371.0 km (3958.8 mi)[9] | ||||||||||||
Equatorial radius | 6378.137 km (3963.191 mi)[10][11] | ||||||||||||
Polar radius | 6356.752 km (3949.903 mi)[12] | ||||||||||||
Flattening | 1/298.257222101 (ETRS89)[13] | ||||||||||||
Circumference |
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Total: 510072000 km2 (196940000 sq mi)[15][n 5]
Land: 148940000 km2 (57510000 sq mi) – 29.2% Ocean: 361132000 km2 (139434000 sq mi) – 70.8% | |||||||||||||
Volume | 1.08321×1012 km3 (2.59876×1011 cu mi)[5] | ||||||||||||
Mass | 5.972168×1024 kg (1.31668×1025 lb)[16] (3.0×10−6 M☉) | ||||||||||||
Mean density | 5.5134 g/cm3 (0.19918 lb/cu in)[5] | ||||||||||||
9.80665 m/s2 (1 g; 32.1740 ft/s2)[17] | |||||||||||||
0.3307[18] | |||||||||||||
11.186 km/s[5] (40270 km/h; 25020 mph) | |||||||||||||
1.0 d (24h 00m 00s) | |||||||||||||
Equatorial rotation velocity | 0.4651 km/s[20] (1674.4 km/h; 1040.4 mph) | ||||||||||||
23.4392811°[4] | |||||||||||||
Albedo | |||||||||||||
Temperature | 287.91 K (14.76 °C) (blackbody temperature)[21] | ||||||||||||
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Surface equivalent dose rate | 0.274 μSv/h[25] | ||||||||||||
Atmosphere | |||||||||||||
Surface pressure | 101.325 kPa (at MSL) | ||||||||||||
Composition by volume |
The atmosphere of Earth consists mostly of nitrogen and oxygen. Greenhouse gases in the atmosphere like carbon dioxide (CO2) trap a part of the energy from the Sun close to the surface. Water vapor is widely present in the atmosphere and forms clouds that cover most of the planet. More solar energy is received by tropical regions than polar regions and is redistributed by atmospheric and ocean circulation. A region's climate is governed not only by latitude but also by elevation and proximity to moderating oceans. In most areas, severe weather, such as tropical cyclones, thunderstorms, and heat waves, occurs and greatly impacts life.
Earth is an ellipsoid with a circumference of about 40,000 km. It is the densest planet in the Solar System. Of the four rocky planets, it is the largest and most massive. Earth is about eight light-minutes away from the Sun and orbits it, taking a year (about 365.25 days) to complete one revolution. The Earth rotates around its own axis in slightly less than a day (in about 23 hours and 56 minutes). The Earth's axis of rotation is tilted with respect to the perpendicular to its orbital plane around the Sun, producing seasons. Earth is orbited by one permanent natural satellite, the Moon, which orbits Earth at 384,400 km (1.28 light seconds) and is roughly a quarter as wide as Earth. Through tidal locking, the Moon always faces the Earth with the same side, which causes tides, stabilizes Earth's axis, and gradually slows its rotation.
Earth, like most other bodies in the Solar System, formed 4.5 billion years ago from gas in the early Solar System. During the first billion years of Earth's history, the ocean formed and then life developed within it. Life spread globally and began to affect Earth's atmosphere and surface, leading to the Great Oxidation Event two billion years ago. Humans emerged 300,000 years ago, and have reached a population of 8 billion today. Humans depend on Earth's biosphere and natural resources for their survival, but have increasingly impacted the planet's environment. Humanity's current impact on Earth's climate and biosphere is unsustainable, threatening the livelihood of humans and many other life, causing widespread extinctions.[27]