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  2. Age of Earth - Wikipedia

    en.wikipedia.org/wiki/Age_of_Earth

    In 1862, the physicist William Thomson, 1st Baron Kelvin published calculations that fixed the age of Earth at between 20 million and 400 million years. [19] [20] He assumed that Earth had formed as a completely molten object, and determined the amount of time it would take for the near-surface temperature gradient to decrease to its present value.

  3. Early Earth - Wikipedia

    en.wikipedia.org/wiki/Early_Earth

    Early Earth also known as proto-earth is loosely defined as encompassing Earth in its first one billion years, or gigayear (Ga, 10 9 y), [1] from its initial formation in the young Solar System at about 4.55 Ga to some time in the Archean eon in approximately 3.5 Ga. [2] On the geologic time scale, this comprises all of the Hadean eon, starting ...

  4. 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

  5. Protogenes - Wikipedia

    en.wikipedia.org/wiki/Protogenes

    Protogenes (/ p r oʊ ˈ t ɒ dʒ ə ˌ n iː z /; Greek: Πρωτογένης; fl. 4th century BC) was an ancient Greek painter, a contemporary rival of Apelles. As with the other famous ancient Greek painters, none of his work has survived, and it is known only from literary references and (brief) descriptions.

  6. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    Late heavy bombardment of the Moon (and probably of the Earth as well) by bolides and asteroids, produced possibly by the planetary migration of Neptune into the Kuiper belt as a result of orbital resonances between Jupiter and Saturn. [5] "Remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia.

  7. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    The Earth of the early Archean may have had a different tectonic style. It is widely believed that the early Earth was dominated by vertical tectonic processes, such as stagnant lid , [ 19 ] [ 20 ] heat-pipe , [ 21 ] or sagduction , [ 22 ] [ 23 ] [ 24 ] which eventually transitioned to plate tectonics during the planet's mid-stage evolution.

  8. Earliest known life forms - Wikipedia

    en.wikipedia.org/wiki/Earliest_known_life_forms

    Earth is the only place in the universe known to harbor life, where it exists in myriad environments. [8] [9] The origin of life on Earth was at least 3.5 billion years ago, possibly as early as 3.8-4.1 billion years ago. [2] [3] [4] Since its emergence, life has persisted in several geological environments.

  9. Dating creation - Wikipedia

    en.wikipedia.org/wiki/Dating_creation

    Creation of the Earth. Wenceslaus Hollar (1607–1677) . Dating creation is the attempt to provide an estimate of the age of Earth or the age of the universe as understood through the creation myths of various religious traditions.