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- Earth - Wikipedia
Earth is the third planet from the Sun and the only astronomical object known to harbor life This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water Almost all of Earth's water is contained in its global ocean, covering 70 8% of Earth's crust
- History of Earth - Wikipedia
Earth formed around 4 54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula [4] [5] [6] Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen Much of Earth was molten because of frequent collisions with other
- Earth - Simple English Wikipedia, the free encyclopedia
Earth is the third planet from the Sun in the Solar System It is one of four rocky planets on the inner side of the Solar System The other three are Mercury, Venus, and Mars Earth is the only planet known to have life on it
- Earth | Definition, Size, Composition, Temperature, Mass, Facts . . .
Earth, third planet from the Sun and the fifth largest planet in the solar system in terms of size and mass Its single most outstanding feature is that its near-surface environments are the only places in the universe known to harbor life Learn more about development and composition of Earth in this article
- Facts About Earth - Science@NASA
Earth is composed of four main layers, starting with an inner core at the planet's center, enveloped by the outer core, mantle, and crust The inner core is a solid sphere made of iron and nickel metals about 759 miles (1,221 kilometers) in radius
- Timeline of Earth estimates - Wikipedia
The pronouncement by Pythagoras (c 570-495 BCE) that the Earth was a sphere prompted his followers to speculate about the size of the Earth sphere Aristotle (384–322 BCE) writes in De caelo, [7] writes that "those mathematicians who try to calculate the size of the earth’s circumference arrive at the figure 400,000 stadia " Archimedes (c 287-212 BCE) felt that the Earth must be smaller at
- Earth - Planet, Atmosphere, Geology | Britannica
With an equatorial radius of 6,378 km (3,963 miles), Earth is the largest of the four inner, terrestrial (rocky) planets, but it is considerably smaller than the gas giants of the outer solar system Earth has a single natural satellite, the Moon, which orbits the planet
- Earth Facts | Surface, Atmosphere, Satellites, History Definition
Earth is estimated to have formed around 4 5 billion years ago – almost one-third of the age of the universe – through accretion from the solar nebula Earth is the third planet from the Sun, at a distance of 1 AU or 147 million km 91 million mi It is the fifth-largest planet in the Solar System, being the largest of the terrestrial planets
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