Earth

"[27] The name Terra /ˈtɛrə/ occasionally is used in scientific writing and especially in science fiction to distinguish humanity's inhabited planet from others,[28] while in poetry Tellus /ˈtɛləs/ has been used to denote personification of the Earth.

[41][42] Between approximately 4.0 and 3.8 Ga, numerous asteroid impacts during the Late Heavy Bombardment caused significant changes to the greater surface environment of the Moon and, by inference, to that of Earth.

[50] The presence of grains of the mineral zircon of Hadean age in Eoarchean sedimentary rocks suggests that at least some felsic crust existed as early as 4.4 Ga, only 140 Ma after Earth's formation.

[56] New continental crust forms as a result of plate tectonics, a process ultimately driven by the continuous loss of heat from Earth's interior.

Over the period of hundreds of millions of years, tectonic forces have caused areas of continental crust to group together to form supercontinents that have subsequently broken apart.

Mammalian life has diversified over the past 66 Mys, and several million years ago, an African ape species gained the ability to stand upright.

[79] Earth's increasing surface temperature will accelerate the inorganic carbon cycle, possibly reducing CO2 concentration to levels lethally low for current plants (10 ppm for C4 photosynthesis) in approximately 100–900 million years.

[83] Even if the Sun were stable and eternal, a significant fraction of the water in the modern oceans would descend into the mantle, due to reduced steam venting from mid-ocean ridges as the core of the Earth slowly cools.

It is composed mostly of iron (32.1% by mass), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%), calcium (1.5%), and aluminium (1.4%), with the remaining 1.2% consisting of trace amounts of other elements.

At approximately 3 Gyr, twice the present-day heat would have been produced, increasing the rates of mantle convection and plate tectonics, and allowing the production of uncommon igneous rocks such as komatiites that are rarely formed today.

[155][156] During magnetic storms and substorms, charged particles can be deflected from the outer magnetosphere and especially the magnetotail, directed along field lines into Earth's ionosphere, where atmospheric atoms can be excited and ionized, causing an aurora.

[177] The most widely accepted theory of the Moon's origin, the giant-impact hypothesis, states that it formed from the collision of a Mars-size protoplanet called Theia with the early Earth.

[185] Some theorists think that without this stabilization against the torques applied by the Sun and planets to Earth's equatorial bulge, the rotational axis might be chaotically unstable, exhibiting large changes over millions of years, as is the case for Mars, though this is disputed.

There are at least seven quasi-satellites, including 469219 Kamoʻoalewa, ranging in diameter from 10 m to 5000 m.[189][190] A trojan asteroid companion, 2010 TK7, is librating around the leading Lagrange triangular point, L4, in Earth's orbit around the Sun.

[215] Other atmospheric functions important to life include transporting water vapor, providing useful gases, causing small meteors to burn up before they strike the surface, and moderating temperature.

[216] This last phenomenon is the greenhouse effect: trace molecules within the atmosphere serve to capture thermal energy emitted from the surface, thereby raising the average temperature.

This water cycle is a vital mechanism for supporting life on land and is a primary factor in the erosion of surface features over geological periods.

Because unfixed hydrogen has a low molecular mass, it can achieve escape velocity more readily, and it leaks into outer space at a greater rate than other gases.

[244] Earth's life has also over time greatly diversified, allowing the biosphere to have different biomes, which are inhabited by comparatively similar plants and animals.

[248]Extreme weather, such as tropical cyclones (including hurricanes and typhoons), occurs over most of Earth's surface and has a large impact on life in those areas.

[249] Many places are subject to earthquakes, landslides, tsunamis, volcanic eruptions, tornadoes, blizzards, floods, droughts, wildfires, and other calamities and disasters.

[252] This is driving changes such as the melting of glaciers and ice sheets, a global rise in average sea levels, increased risk of drought and wildfires, and migration of species to colder areas.

[253] Originating from earlier primates in Eastern Africa 300,000 years ago humans have since been migrating and with the advent of agriculture in the 10th millennium BC increasingly settling Earth's land.

Since the second half of the 20th century, some hundreds of humans have temporarily stayed beyond Earth, a tiny fraction of whom have reached another celestial body, the Moon.

[263] Most of these states together form the United Nations, the leading worldwide intergovernmental organization,[264] which extends human governance over the ocean and Antarctica, and therefore all of Earth.

[270] Earth's biosphere produces many useful biological products for humans, including food, wood, pharmaceuticals, oxygen, and the recycling of organic waste.

Through activities such as the burning of fossil fuels, humans have been increasing the amount of greenhouse gases in the atmosphere, altering Earth's energy budget and climate.

Of the nine identified boundaries, five have been crossed: Biosphere integrity, climate change, chemical pollution, destruction of wild habitats and the nitrogen cycle are thought to have passed the safe threshold.

[283] The Gaia hypothesis, developed in the mid-20th century, compared Earth's environments and life as a single self-regulating organism leading to broad stabilization of the conditions of habitability.

[284][285][286] Images of Earth taken from space, particularly during the Apollo program, have been credited with altering the way that people viewed the planet that they lived on, called the overview effect, emphasizing its beauty, uniqueness and apparent fragility.

A 2012 artistic impression of the early Solar System 's protoplanetary disk from which Earth and other Solar System bodies were formed
Pale orange dot , an artist's impression of Early Earth , featuring its tinted orange methane -rich early atmosphere [ 49 ]
An artist's impression of the Archean , the eon after Earth's formation, featuring round stromatolites , which are early oxygen-producing forms of life from billions of years ago. After the Late Heavy Bombardment , Earth's crust had cooled, its water-rich barren surface is marked by continents and volcanoes , with the Moon still orbiting Earth half as far as it is today, appearing 2.8 times larger and producing strong tides . [ 72 ]
A dark gray and red sphere representing the Earth lies against a black background to the right of an orange circular object representing the Sun
Conjectured illustration of the scorched Earth after the Sun has entered the red giant phase, about 5–7 billion years in the future
Earth's western hemisphere showing topography relative to Earth's center instead of to mean sea level , as in common topographic maps
A composite image of Earth, with its different types of surface discernible: Earth's surface dominating Ocean (blue), Africa with lush (green) to dry (brown) land and Earth's polar ice in the form of Antarctic sea ice (grey) covering the Antarctic or Southern Ocean and the Antarctic ice sheet (white) covering Antarctica .
Shows the extent and boundaries of tectonic plates, with superimposed outlines of the continents they support
Earth's major plates , which are: [ 121 ]
A map of heat flow from Earth's interior to the surface of Earth's crust, mostly along the oceanic ridges
Diagram showing the magnetic field lines of Earth's magnetosphere. The lines are swept back in the anti-solar direction under the influence of the solar wind.
A schematic view of Earth's magnetosphere with solar wind flowing from left to right
Satellite time lapse imagery of Earth's rotation showing axis tilt
Exaggerated illustration of Earth's elliptical orbit around the Sun, marking that the orbital extreme points ( apoapsis and periapsis ) are not the same as the four seasonal extreme points, the equinox and solstice
Earth's axial tilt causing different angles of seasonal illumination at different orbital positions around the Sun
Earth and the Moon as seen from Mars by the Mars Reconnaissance Orbiter
A computer-generated image mapping the prevalence of artificial satellites and space debris around Earth in geosynchronous and low Earth orbit
A view of Earth with its global ocean and cloud cover , which dominate Earth's surface and hydrosphere ; at Earth's polar regions, its hydrosphere forms larger areas of ice cover.
A view of Earth with different layers of its atmosphere visible: the troposphere with its clouds casting shadows, a band of stratospheric blue sky at the horizon, and a line of green airglow of the lower thermosphere around an altitude of 100 km, at the edge of space
Earth's night-side upper atmosphere appearing from the bottom as bands of afterglow illuminating the troposphere in orange with silhouettes of clouds, and the stratosphere in white and blue. Next the mesosphere (pink area) extends to the orange and faintly green line of the lowest airglow , at about one hundred kilometers at the edge of space and the lower edge of the thermosphere (invisible). Continuing with green and red bands of aurorae stretching over several hundred kilometers.
An animation of the changing density of productive vegetation on land (low in brown; heavy in dark green) and phytoplankton at the ocean surface (low in purple; high in yellow)
A High Desert storm in the Mojave
A composite image of artificial light emissions at night on a map of Earth
Earth's land use for human agriculture in 2019
The graph from 1880 to 2020 shows natural drivers exhibiting fluctuations of about 0.3 degrees Celsius. Human drivers steadily increase by 0.3 degrees over 100 years to 1980, then steeply by 0.8 degrees more over the past 40 years.
Change in average surface air temperature and drivers for that change. Human activity has caused increased temperatures, with natural forces adding some variability. [ 275 ]
Woman seeing the Earth from space through a window
Tracy Caldwell Dyson , a NASA astronaut, observing Earth from the Cupola module at the International Space Station on 11 September 2010
The Sun, the planets, their moons, and several trans-Neptunian objects The Sun Mercury Venus The Moon Earth Mars Phobos and Deimos Ceres The main asteroid belt Jupiter Moons of Jupiter Rings of Jupiter Saturn Moons of Saturn Rings of Saturn Uranus Moons of Uranus Rings of Uranus Neptune Moons of Neptune Rings of Neptune Pluto Moons of Pluto Haumea Moons of Haumea Makemake S/2015 (136472) 1 The Kuiper Belt Eris Dysnomia The Scattered Disc The Hills Cloud The Oort Cloud