Terminology: Dwarf Planet vs. ProtoPlanet

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Discussion Overview

The discussion revolves around the terminology used in a Grade 9 textbook regarding the classification of celestial objects, specifically the distinction between "dwarf planets" and "protoplanets." Participants explore the implications of these terms within the context of planetary formation and classification.

Discussion Character

  • Conceptual clarification, Debate/contested

Main Points Raised

  • One participant suggests that "protoplanet" refers to planetesimals in a young, forming system with potential to develop into planets, while "dwarf planets" are considered to have reached a stable state.
  • Another participant agrees, emphasizing that the term "protoplanet" implies an ongoing formation process, which does not apply to objects like Pluto.
  • A third participant expresses a desire for an authoritative answer to support their position in discussions with an editor.
  • One participant notes that the International Astronomical Union (IAU) classifies Pluto as a dwarf planet and mentions that "protoplanet" is typically used in discussions about proto-planetary disks.

Areas of Agreement / Disagreement

Participants generally agree on the distinction between "dwarf planets" and "protoplanets," but there is no consensus on the appropriateness of the textbook wording or the implications of these terms.

Contextual Notes

The discussion highlights potential ambiguities in the definitions of "dwarf planet" and "protoplanet," as well as the reliance on authoritative sources for clarification.

DaveC426913
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For a Grade 9 textbook:

"Many more objects exist in the solar system besides the eight major planets. These are smaller and include moons, comets, protoplanets, such as Pluto, and tiny grains of dust and ice."

Is this acceptably-worded or is it misleading?

My take is that the term "protoplanet" refers to planetesimals that are part of a young still-forming system and have the potential to grow into planets. "Dwarf planets" are pretty much all they're ever going to be.
 
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I agree. Protoplanet suggests they're still in the process of forming, which is certainly not the case.
 
I'm hoping for an authoritative answer from someone who knows these things so I can defend it to the editor.
 
The IAU discussion about pluto calls them dwarf planets.
I have only seen protoplanet in the context of a proto-planetary disk
 

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