protoplanet
noun
pro·to·plan·et
ˈprō-tō-ˌpla-nət 
: a hypothetical whirling gaseous mass within a giant cloud of gas and dust that rotates around a sun and is believed to give rise to a planet
Examples of protoplanet in a Sentence
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The most popular theory says that about 4.5 billion years ago, a Mars-size protoplanet slammed into Earth.
—
Kenneth Chang, New York Times, 1 Nov. 2023
But scientists have lacked smoking-gun evidence like a crater or pieces of the protoplanet, named Theia.
—Kenneth Chang, New York Times, 1 Nov. 2023
Further afield, one leading theory to account for certain quirks of our solar system’s architecture posits that early shifts in the orbits of Jupiter and Saturn sparked brutal cascades of collisions between nascent protoplanets.
—Lyndie Chiou, Scientific American, 25 Oct. 2023
The new measurements are significant as this is the first time water has been detected in a region where two or more protoplanets are known to exist.
—Jack Birle, Washington Examiner, 25 July 2023
See all Example Sentences for protoplanet 
Kenneth Chang, New York Times, 1 Nov. 2023
But scientists have lacked smoking-gun evidence like a crater or pieces of the protoplanet, named Theia.
—Kenneth Chang, New York Times, 1 Nov. 2023
Further afield, one leading theory to account for certain quirks of our solar system’s architecture posits that early shifts in the orbits of Jupiter and Saturn sparked brutal cascades of collisions between nascent protoplanets.
—Lyndie Chiou, Scientific American, 25 Oct. 2023
The new measurements are significant as this is the first time water has been detected in a region where two or more protoplanets are known to exist.
—Jack Birle, Washington Examiner, 25 July 2023
See all Example Sentences for protoplanet
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“Protoplanet.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/protoplanet. Accessed 26 Jul. 2024.
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protoplanet
noun
pro·to·plan·et
ˈprōt-ō-ˌplan-ət
: a whirling mass of gas that rotates around a star and is believed to become a planet
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