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  2. Accretion (astrophysics) - Wikipedia

    en.wikipedia.org/wiki/Accretion_(astrophysics)

    The initial collapse of a solar-mass protostellar nebula takes around 100,000 years. [ 8 ] [ 9 ] Every nebula begins with a certain amount of angular momentum . Gas in the central part of the nebula, with relatively low angular momentum, undergoes fast compression and forms a hot hydrostatic (non-contracting) core containing a small fraction of ...

  3. Nebular hypothesis - Wikipedia

    en.wikipedia.org/wiki/Nebular_hypothesis

    The widely accepted modern variant of the nebular theory is the solar nebular disk model (SNDM) or solar nebular model. [1] It offered explanations for a variety of properties of the Solar System, including the nearly circular and coplanar orbits of the planets, and their motion in the same direction as the Sun's rotation.

  4. Chondrule - Wikipedia

    en.wikipedia.org/wiki/Chondrule

    Chondrule formation and accretion processes in the early solar nebula – Clues from noble gases in different constituents of unequilibrated chondrites, Der Andere Verlag, Osnabrück, ISBN 3-89959-055-4

  5. Formation and evolution of the Solar System - Wikipedia

    en.wikipedia.org/wiki/Formation_and_evolution_of...

    Pierre-Simon Laplace, one of the originators of the nebular hypothesis. Ideas concerning the origin and fate of the world date from the earliest known writings; however, for almost all of that time, there was no attempt to link such theories to the existence of a "Solar System", simply because it was not generally thought that the Solar System, in the sense we now understand it, existed.

  6. Accretion disk - Wikipedia

    en.wikipedia.org/wiki/Accretion_disk

    An accretion disk is a structure (often a circumstellar disk) formed by diffuse material [a] in orbital motion around a massive central body. ... Solar nebula; Spin-flip;

  7. Frost line (astrophysics) - Wikipedia

    en.wikipedia.org/wiki/Frost_line_(astrophysics)

    In astronomy or planetary science, the frost line, also known as the snow line or ice line, is the minimum distance from the central protostar of a solar nebula where the temperature is low enough for volatile compounds such as water, ammonia, methane, carbon dioxide and carbon monoxide to condense into solid grains, which will allow their accretion into planetesimals.

  8. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the Solar System. Initially, Earth was molten due to extreme volcanism and frequent collisions with other bodies.

  9. Stellar evolution - Wikipedia

    en.wikipedia.org/wiki/Stellar_evolution

    A protostar continues to grow by accretion of gas and dust from the molecular cloud, becoming a pre-main-sequence star as it reaches its final mass. Further development is determined by its mass. Mass is typically compared to the mass of the Sun: 1.0 M ☉ (2.0 × 10 30 kg) means 1 solar mass.