Talk:Geophysical definition of planet

Latest comment: 2 years ago by Dax Kirk in topic Alternate geophysical definitions

planetary body

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I merged this article here, since all it was was a statement of Stern's 2002 definition. The only change since is the 2006 IAU declaration, but Stern's definition is essentially the same now as then. — kwami (talk) 11:13, 16 October 2020 (UTC)Reply

A nice example of the geophysical definition

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Dark Companions of Stars, Peter van de Kamp (1986).

Most of Jupiter's satellites are only a few hundred kilometers in diameter, and most likely are captured asteroids. The four Galilean satellites (Io, Europ[a], Callisto, and Ganymede, with diameters 3640, 3100, 5000, and 5270 km) are much larger, comparable in size with our Moon (3476 km) and with Mercury (4880 km). These four satellites physically qualify as planets. The same holds for the larger satellites Titan (5800 km) of Saturn, and Triton (6000 km) of Neptune.

(Also cool for the old huge Titan and huge Triton.) Double sharp (talk) 23:36, 26 October 2021 (UTC)Reply

Alternate geophysical definitions

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Hi! I wanted to mention a few things that are related under one umbrella. First, the intro seemingly contradicted itself by giving a definition for "planet" and, right after that, stating that there is no formal definition and that, in fact, "there are various definitions in use among professional planetary scientists and astronomers." I tried to rework the introduction to make it consistent and not contradict itself. Second...I guess just want to check and see exactly what is meant by "Geophysical definition of planet." According to my understanding, a geophysical definition would include any and all definitions that are widely accepted by professional geoscientists. I did some google research to see if there were other definitions geoscientists used (as the article noted in the intro), and it became immediately clear that some geoscientists do use alternate definitions. For example, I turned up a textbook titled "Physical Geology" that was written by geoscientists and uses the IAU definition of a planet. The authors didn't say they were giving the "astronomy definition of a planet." They are geologists writing about the definition of "planet." How is it not a geological definition? Not noting that some geologists don't use Stern's definition and only listing his as THE definitive geophysical definition of a planet seems like an omission. I could be wrong here though? Some people feel pretty passionately about this topic, so just wanted to post this so it was clear they were good-faith edits and open the floor for discussion....lest people go on a reverting spree and post yelly comments at me :) Dax Kirk (talk) 03:09, 10 December 2021 (UTC)Reply