What does planetesimal mean?

Definitions for planetesimal
ˌplæn ɪˈtɛs ə məlplan·etes·i·mal

Here are all the possible meanings and translations of the word planetesimal.

Princeton's WordNet

  1. planetesimalnoun

    one of many small solid celestial bodies thought to have existed at an early stage in the development of the solar system


  1. planetesimalnoun

    Any of many small, solid astronomical objects, that orbit a star and form protoplanets through mutual gravitational attraction


  1. Planetesimal

    Planetesimals are solid objects thought to exist in protoplanetary disks and in debris disks. A widely accepted theory of planet formation, the so-called planetesimal hypothesis of Viktor Safronov, states that planets form out of cosmic dust grains that collide and stick to form larger and larger bodies. When the bodies reach sizes of approximately one kilometer, then they can attract each other directly through their mutual gravity, enormously aiding further growth into moon-sized protoplanets. This is how planetesimals are often defined. Bodies that are smaller than planetesimals must rely on Brownian motion or turbulent motions in the gas to cause the collisions that can lead to sticking. Alternatively, planetesimals can form in a very dense layer of dust grains that undergoes a collective gravitational instability in the mid-plane of a protoplanetary disk. Many planetesimals eventually break apart during violent collisions, as may have happened to 4 Vesta and 90 Antiope, but a few of the largest planetesimals can survive such encounters and continue to grow into protoplanets and later planets. It is generally believed that about 3.8 billion years ago, after a period known as the Late Heavy Bombardment, most of the planetesimals within the Solar System had either been ejected from the Solar System entirely, into distant eccentric orbits such as the Oort cloud, or had collided with larger objects due to the regular gravitational nudges from the giant planets. A few planetesimals may have been captured as moons, such as Phobos and Deimos, and many of the small high-inclination moons of the giant planets.

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  1. Chaldean Numerology

    The numerical value of planetesimal in Chaldean Numerology is: 7

  2. Pythagorean Numerology

    The numerical value of planetesimal in Pythagorean Numerology is: 1

Images & Illustrations of planetesimal

  1. planetesimalplanetesimalplanetesimalplanetesimalplanetesimal

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    the act of taking something from someone unlawfully
    • A. hypostatization
    • B. larceny
    • C. scalawag
    • D. squint-eye

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