from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. An astronomical object, approximately the size of the Moon, formed from the mutual gravitational attraction of planetesimals; they are thought to collide with each other and slowly form planets


Sorry, no etymologies found.


  • As it is, Vesta is 330 miles across and is classified as a "protoplanet."

    Yahoo! News: Business - Opinion

  • Scientists call Vesta a "protoplanet" because it almost formed into a planet like Mars or Earth.

    US Spacecraft to Rendezvous with Asteroid

  • Chunks of the protoplanet have been knocked off during collisions with other space rocks.

    US Spacecraft to Rendezvous with Asteroid

  • New close-up images of Pallas from the Hubble Space Telescope reveal that the second largest asteroid in the solar system appears to be a protoplanet, as well.

    Asteroid Pallas is Also a Protoplanet | Universe Today

  • We may discover some borderline Kuiper Belt Objects that also fall into this protoplanet category. » Between Asteroids and Planets: A New Category

  • In the scientific community a widespread theory is that the moon was created when a protoplanet called Theia collided with Earth, and that that was also the catalyst necessary for life here, that it changed the chemical and climatic makeup suffiecently to birth simple early life like molecules that eventually evolved into proper simple organisms and after millions of years, us.

    Your Creation Museum Report « Whatever

  • He cut in maximum magnification on the screens, and the surface of the little protoplanet of frozen gases leaped up toward him.

    Starchild Omnibus

  • It was a tiny blip, settling down feather-light toward the surface of the snowball protoplanet.

    Starchild Omnibus

  • In this handout image released July 14, 2011 by NASA, the Dawn spacecraft obtained this image with its framing camera on July 9, 2011 of the protoplanet Vesta.

    Reuters: Top News

  • Scientists consider this onion-like asteroid to be a protoplanet, a relic from an early phase of planet formation more than 41 /2 billion years ago.

    Yahoo! News: Business - Opinion


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