from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Any of innumerable small bodies thought to have orbited the sun during the formation of the planets.

from Wiktionary, Creative Commons Attribution/Share-Alike License

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

from The Century Dictionary and Cyclopedia

  • Of or pertaining to a minute planet or planetary body.
  • n. One of the minute bodies moving in planetary orbits, from time to time overtaking each other and coalescing, and so gradually building up the planets, according to the planetesimal hypothesis.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

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


from The American Heritage® Dictionary of the English Language, 4th Edition

planet + (infinit)esimal.


  • The Murchison meteorite, as it is now known, is a fragment of a "planetesimal" or small, solid fragment that condensed out of the solar nebula as the solar system formed.

    In the Primordial Soup

  • With all those Masonic symbols on its cover, I figured that CULTS, CONSPIRACIES AND SECRET SOCIETIES stood a small chance of being captured by THE LOST SYMBOL's commercial gravity, much as a tiny planetesimal can get pulled into a gas giant's orbit.

    Boing Boing

  • A handful of components, scraping iron ore from a planetesimal.

    Jason Stoddard, Strange and Happy » 2010 » April

  • Thomas Chrowder Chamberlin (1843-1928) was a respected and influential American geologist and science educator who supported the concepts of multiple glaciation and planetesimal origin of the Earth, and was among the first to emphasize carbon dioxide as a major regulator of Earth's temperature.

    Climate Change Biographies

  • Chamberlin disputed Kelvin's assumption of simple cooling from a molten origin because he was already formulating his own cold, planetesimal origin.

    Chamberlin, Thomas Chrowder

  • An astronaut who had made the impossibly long journey and knew precisely where to look would have seen it as a black dimple on the rocky/icy regolith of the host planetesimal.


  • Tendrils of it forced themselves into the loose material of the planetesimal, mining it for carbonaceous molecules.


  • "We believe Phoebe is a good example of the fundamental building blocks of planets -- an icy planetesimal," he said, noting that such objects once filled the solar system.

    Saturn Moon Reveals Its Secrets

  • THE most elaborate structure yet proposed to explain the origin of the solar system is the planetesimal hypothesis by

    Popular Science Monthly Oct, Nov, Dec, 1915 — Volume 86

  • The authors call attention to the fact that the Sun's equator is inclined at a small angle, 7 degrees, to the common planes of the planetary system, and Chamberlin holds this to be one of the strong points in favor of the planetesimal hypothesis.

    Popular Science Monthly Oct, Nov, Dec, 1915 — Volume 86


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