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THE ORIGIN OF THE SOLAR SYSTEM - Coggle Diagram

- - - - [Geocentric model/theory states that the planets, moon, stars, sun revolves around the Earth that is located at the center.The model was an accepted explanation of the different motions in the universe.It is proposed by Claudius Ptolemy,a Greek mathematician, astronomer and geographer.
        
        Ancienct greeeks such as Aristotle beleived that the universe was perfect and finite, with the Earth at the exact center.
  - - - Heliocentric model states that the sun is the center of our solar sytem. It is also stated that each heavenly body inhabited a sphere encapsulating the sun. This model is made by NicolausCopernicus, the father of modern astronomy, he was the first modern European scientist to propose that Earth and other planets revolve around the sun.
        
        By 1514, Copernicus began circulating copies of his seven principles, amongst his friends, many of whom were
        fellow astronomers and scholars.
        
        Celestial bodies do not all revolve around a single point,The center of Earth is the center of the lunar sphere—the orbit of the moon
        around Earth and All the spheres rotate around the sun, which is near the center of the universe.These are just some of his seven principles.
- - - - Protoplanet, in astronomical theory, a hypothetical eddy in a whirling cloud of gas or dust that becomes a planet by condensation during formation of a solar system.
        
        Many astronomers support this
        theory because observations through large telescopes have revealed numerous true
        nebulas between the stars.
        
        The protoplanet hypothesis is generally acceptable to most scientists because it explainsmany of the known facts about
        the solar system.
        
        As the protoplanets grew to become planets, parts of them melted due to radioactivity, gravitational influences, and collisions. Where the objects had melted, the composition of the planets changed. Heavier elements sank, forming the cores of the planets, and lighter objects rose to the surface.
        
        W. H. McCrea proposed the protoplanet theory, in which the Sun and planets individually coalesced from matter within the same cloud, with the smaller planets later captured by the Sun's larger gravity.
        
        W. H. McCrea
    - - According to the nebular theory, stars form in massive and dense clouds of molecular
        hydrogen—giant molecular clouds (GMC)These clouds are gravitationally unstable, and
        matter coalesces within them to smaller denser clumps, which then rotate, collapse, and
        form stars.
        
        The nebular hypothesis is the idea that a spinning cloud of dust made of mostly light elements, called a nebula, flattened into a protoplanetary disk, and became a solar system consisting of a star with orbiting planets
    - - It is developed by T. C. Chamberlin and F. R. Moulton in the early part of
        the 20th cent.
        
        F.R. MOULTON
        
        T.C. CHAMBERLIN
      - The Tidal Theory is a
        variation of the planetesimal concept. It suggests that a huge tidal wave, raised on the
        sun by a passing star, was drawn into a long filament and became detached from the
        principal mass.
        
        It is proposed by James Jeans and Harold Jeffreys in 1918
        
        JAMES JEANS
        
        HAROLD JEFFREYS