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kergonath • today at 8:32 PM • 1 reply • view on HN

So, a factor of 14.4 is enough to put the line between Ceres and Pluto, but a factor of 23.0 is not enough to put it between Pluto and Mercury?

Yes, those classifications are arbitrary, but then any classification is. If you want to consider Pluto as a planet, you have to include quite a lot of other bodies, which are all qualitatively and quantitatively different from the 8 (which themselves are in 2 qualitatively and quantitatively different groups. Or 3, depending on who you ask).

In the grand scheme of things, it does not matter and astronomers won’t care about the general public’s feelings. It is utterly pointless to get worked up about these things.


Replies

cwillu • today at 9:08 PM

The problem is not experts having precise terminology in technical settings; the problem is the army of “experts” who will descend upon you if you use the incorrect arbitrary term in colloquial settings. The same sort that will descend on you if you dare refer to a planet orbiting a different star as a planet, not an exo-planet.