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  2. Planet - Wikipedia

    en.wikipedia.org/wiki/Planet

    The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion.

  3. Formation and evolution of the Solar System - Wikipedia

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

    By 10 million years, gas in the protoplanetary disc has been blown away, and outer planet formation is likely complete. [38] 10 million – 100 million years 4.5–4.6 bya: Terrestrial planets and the Moon form. Giant impacts occur. Water delivered to Earth. [2] Main sequence 50 million years 4.5 bya: Sun becomes a main-sequence star. [32] 200 ...

  4. Retrograde and prograde motion - Wikipedia

    en.wikipedia.org/wiki/Retrograde_and_prograde_motion

    If formed in the gravity field of a planet as the planet is forming, a moon will orbit the planet in the same direction as the planet is rotating and is a regular moon. If an object is formed elsewhere and later captured into orbit by a planet's gravity, it can be captured into either a retrograde or prograde orbit depending on whether it first ...

  5. Nebular hypothesis - Wikipedia

    en.wikipedia.org/wiki/Nebular_hypothesis

    [31] [68] Searches as of 2011 have found that core accretion is likely the dominant formation mechanism. [68] Giant planet core formation is thought to proceed roughly along the lines of the terrestrial planet formation. [20] It starts with planetesimals that undergo runaway growth, followed by the slower oligarchic stage. [65]

  6. History of Solar System formation and evolution hypotheses

    en.wikipedia.org/wiki/History_of_Solar_System...

    French philosopher and mathematician René Descartes was the first to propose a model for the origin of the Solar System in his book The World, written from 1629 to 1633.. In his view, the universe was filled with vortices of swirling particles, and both the Sun and planets had condensed from a large vortex that had contracted, which he thought could explain the circular motion of the plane

  7. 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.

  8. Solar System - Wikipedia

    en.wikipedia.org/wiki/Solar_System

    Thus, the Sun occupies 0.00001% (1 part in 10 7) of the volume of a sphere with a radius the size of Earth's orbit, whereas Earth's volume is roughly 1 millionth (10 −6) that of the Sun. Jupiter, the largest planet, is 5.2 AU from the Sun and has a radius of 71,000 km (0.00047 AU; 44,000 mi), whereas the most distant planet, Neptune, is 30 AU ...

  9. Kepler-1649c - Wikipedia

    en.wikipedia.org/wiki/Kepler-1649c

    Kepler-1649c is an Earth-sized exoplanet, likely rocky, orbiting within the habitable zone of the red dwarf star Kepler-1649, the outermost planet of the planetary system discovered by Kepler’s space telescope. It is located about 301 light-years (92 pc) away from Earth, in the constellation of Cygnus. [3]