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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.
Knowledge of the location of Earth has been shaped by 400 years of telescopic observations, and has expanded radically since the start of the 20th century. Initially, Earth was believed to be the center of the Universe , which consisted only of those planets visible with the naked eye and an outlying sphere of fixed stars . [ 1 ]
15.049 to 17.675 billion light-years. (present comoving distance) [4] The Hercules–Corona Borealis Great Wall (HCB) [1][5] or simply the Great Wall[6] is a galaxy filament that is the largest known structure in the observable universe, measuring approximately 10 billion light-years in length (the observable universe is about 93 billion light ...
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity. [ 1 ][ 2 ] The word is derived from the Greek galaxias (γαλαξίας), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System.
The Milky Way is approximately 890 billion to 1.54 trillion times the mass of the Sun in total (8.9 × 10 11 to 1.54 × 10 12 solar masses), [7][8][9] although stars and planets make up only a small part of this. Estimates of the mass of the Milky Way vary, depending upon the method and data used.
Orion Arm – a spiral arm of the Milky Way. Solar System – the Sun and the objects that orbit it, including eight planets, the third planet closest to the Sun being Earth. Earth's orbit – path through which the Earth travels around the Sun. The average distance between the Earth and the Sun is 149.60 million kilometers (92.96 million miles).
720,000 km/h (450,000 mi/h) [10] Orbital period. ~230 million years [10] The Solar System[d] is the gravitationally bound system of the Sun and the objects that orbit it. [11] It was formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, forming the Sun and a protoplanetary disc.
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.