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  2. Rare Earth hypothesis - Wikipedia

    en.wikipedia.org/wiki/Rare_Earth_hypothesis

    The Rare Earth hypothesis argues that planets with complex life, like Earth, are exceptionally rare.. In planetary astronomy and astrobiology, the Rare Earth hypothesis argues that the origin of life and the evolution of biological complexity, such as sexually reproducing, multicellular organisms on Earth, and subsequently human intelligence, required an improbable combination of astrophysical ...

  3. Cosmogony - Wikipedia

    en.wikipedia.org/wiki/Cosmogony

    The Big Bang theory, which explains the Evolution of the Universe from a hot and dense state, is widely accepted by physicists. In astronomy, cosmogony is the study of the origin of particular astrophysical objects or systems, and is most commonly used in reference to the origin of the universe, the Solar System, or the Earth–Moon system.

  4. Timeline of cosmological theories - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_cosmological...

    Aryabhatta puts forward the theory of rotation of the Earth in its own axis and explained day and night was caused by the diurnal rotation of the Earth. He models a geocentric universe with the sun, moon, and planets following circular and eccentric orbits with epicycles. [48] 5th century – The Jewish talmud gives an argument for finite ...

  5. History of research into the origin of life - Wikipedia

    en.wikipedia.org/wiki/History_of_research_into...

    The underlying hypothesis held by Oparin, Haldane, Bernal, Miller and Urey, for instance, was that multiple conditions on the primeval Earth favoured chemical reactions that synthesized the same set of complex organic compounds from such simple precursors. Bernal coined the term biopoiesis in 1949 to refer to the origin of life. [33]

  6. Panspermia - Wikipedia

    en.wikipedia.org/wiki/Panspermia

    Panspermia (from Ancient Greek πᾶν (pan) 'all' and σπέρμα (sperma) 'seed') is the hypothesis that life exists throughout the Universe, distributed by space dust, [1] meteoroids, [2] asteroids, comets, [3] and planetoids, [4] as well as by spacecraft carrying unintended contamination by microorganisms, [5] [6] [7] known as directed ...

  7. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    The PAH world hypothesis is a speculative hypothesis that proposes that polycyclic aromatic hydrocarbons (PAHs), known to be abundant in the universe, [177] [178] [179] including in comets, [180] and assumed to be abundant in the primordial soup of the early Earth, played a major role in the origin of life by mediating the synthesis of RNA ...

  8. Chronology of the universe - Wikipedia

    en.wikipedia.org/wiki/Chronology_of_the_universe

    The chronology of the universe describes the history and future of the universe according to Big Bang cosmology. Research published in 2015 estimates the earliest stages of the universe's existence as taking place 13.8 billion years ago, with an uncertainty of around 21 million years at the 68% confidence level.

  9. Primordial soup - Wikipedia

    en.wikipedia.org/wiki/Primordial_soup

    Primordial soup, also known as prebiotic soup, is the hypothetical set of conditions present on the Earth around 3.7 to 4.0 billion years ago. It is an aspect of the heterotrophic theory (also known as the Oparin–Haldane hypothesis) concerning the origin of life, first proposed by Alexander Oparin in 1924, and J. B. S. Haldane in 1929.