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  2. Origin of water on Earth - Wikipedia

    en.wikipedia.org/wiki/Origin_of_water_on_Earth

    The mass of Earth's oceans is estimated to be 1.37 × 10 21 kg, which is 0.023% of the total mass of Earth, 6.0 × 10 24 kg. An additional 5.0 × 10 20 kg of water is estimated to exist in ice, lakes, rivers, groundwater, and atmospheric water vapor. [20] A significant amount of water is also stored in Earth's crust, mantle, and core.

  3. History of Earth - Wikipedia

    en.wikipedia.org/wiki/History_of_Earth

    The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, [34] [35] [36] soon after the formation of the Earth's crust and the Earth

  4. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    The Precambrian includes approximately 90% of geologic time. It extends from 4.6 billion years ago to the beginning of the Cambrian Period (about 539 Ma).It includes the first three of the four eons of Earth's prehistory (the Hadean, Archean and Proterozoic) and precedes the Phanerozoic eon.

  5. Astronomers find new link between water and planet formation

    www.aol.com/astronomers-between-water-planet...

    Astronomers have found water in the disc around a young star where planets may be forming, revealing a new link between the key ingredient for life and planet formation. ... located 450 light ...

  6. Earth - Wikipedia

    en.wikipedia.org/wiki/Earth

    Most of Earth's surface is ocean water: 70.8% or 361 million km 2 (139 million sq mi). [96] This vast pool of salty water is often called the world ocean, [97] [98] and makes Earth with its dynamic hydrosphere a water world [99] [100] or ocean world. [101] [102] Indeed, in Earth's early history the ocean may have covered Earth completely. [103]

  7. Hadean - Wikipedia

    en.wikipedia.org/wiki/Hadean

    The Hadean (/ h eɪ ˈ d iː ə n, ˈ h eɪ d i ə n / hay-DEE-ən, HAY-dee-ən) is the first and oldest of the four known geologic eons of Earth's history, starting with the planet's formation about 4.6 billion years ago [4] [5] (estimated 4567.30 ± 0.16 million years ago [2] set by the age of the oldest solid material in the Solar System — protoplanetary disk dust particles — found as ...

  8. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    The earliest Earth crust probably forms similarly out of similar material. On Earth the pluvial period starts, in which the Earth's crust cools enough to let oceans form. c. 4,404 Ma – First known mineral, found at Jack Hills in Western Australia. Detrital zircons show presence of a solid crust and liquid water.

  9. Early Greek cosmology - Wikipedia

    en.wikipedia.org/wiki/Early_Greek_cosmology

    Near the edges of the earth is a region inhabited by fantastical creatures, monsters, and quasi-human beings. [6] Once one reaches the ends of the earth they find it to be surrounded by and delimited by an ocean (), [7] [8] as is seen in the Babylonian Map of the World, although there is one main difference between the Babylonian and early Greek view: Oceanus is a river and so has an outer ...