Once again, some people are reading sci-fi books that criticize just this thing and seeing it as a roadmap…
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From the Sun out to Neptune, there are about 30 worlds that satisfy this definition of “planet”:
- The 8 big ones: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
- The 18 or 19 round moons: Earth’s Moon; Jupiter’s Io, Europa, Ganymede, and Callisto; Saturn’s Mimas, Enceladus, Tethys, Dione, Rhea, Titan, and Iapetus; Uranus’ Miranda, Ariel, Umbriel, Titania, and Oberon; Neptune’s Triton and possibly Proteus.
- A few of the 4 largest asteroids: Ceres and possibly Pallas and Hygeia, but possibly not Vesta.
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The hallmark of a good definition – something so imprecise that you can’t even tell what it applies to, separating objects that are similar in every other way, but at least you keep the American planet. That’s what counts. 
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… ooh we could make a list
Alien
Outland
Total Recall
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Two groups of people deciding the classes of things that interest them, and then deciding which objects belong in which class. And then, a third group of people controlling the purse strings.
Was pluto interesting because it was a larger version of Arrokoth? Was it less interesting because it at failed to clear its orbit? Or did it have things like Plate tectonics?
The idea that we should be classifying things not based on actual similarity, but how interesting they are, is frankly so alien to me that I don’t know how to answer. Are objects other than planets not interesting? I never thought they weren’t interesting. Does how interesting Vesta is change if we pick a threshold where it’s “barely round” or “barely not round”?
Luna-10 will select a group of companies that have an idea for lunar services, allowing them to work together to develop an integrated system for lunar communication, energy, transmission or other building blocks necessary
What we’ve got now doesn’t work when the power goes out, when the temperatures are too hot or too cold, when the lines get wet, when the wind blows really hard… 
Is it wrong that I’m hoping after luring these companies into figuring out how to keep things running in harsh conditions on the Moon, Biden turns around and says “Great, now how about you implement all that here on Earth first!”
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Asteroid mining and orbital refining are key components to a truly post-scarcity future.
It makes me incredibly sad that crony capitalism is the path we’re choosing to get there.
There must be a more convenient source for green cheese.
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Suppose we lived in the pre New Horizons days, and somehow this nomenclature problem had occurred earlier.
Would you rather send one probe to Pluto, or one probe to seven Kuiper Belt objects of middling size?
If Pluto is nothing more than a Kuiper Belt object, there would be much more of case for skipping it in favor of multiple targets.
If it’s a planet, there’s more of a case for sending a probe to Pluto and missing the opportunity to visit more than one or two KBOs.
Pluto is Pluto – the most massive of the objects in the innermost Kuiper belt, big enough to be spherical and with a small system of moons, and one of various captured in eccentric orbits in resonance with Neptune. Both whether it’s interesting to study and how it’s labeled should reflect that reality. The idea of using taxonomy as some kind of mission PR instead of describing the world strikes me as anti-scientific and distasteful in the extreme. Not everything needs to be about god damn spin.
Honestly if I thought being round mattered that much, I would rather send a probe to seven middling Kuiper Belt objects, because without that we have no idea whether they’re round or not. How would you not want to check out whether they’re “geophysical planets” or not? 
Hard to take the spin out of orbital mechanics.
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With enough campaign donations… anything can happen.
“Want Buck Rogers?”
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strictly speaking, that would have been based on mass
“A planet is a celestial body that (a) is in or- bit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit.”
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It seemed like such a promising business plan. But I guess Wallace must have blown all his profits on buying those trousers from NASA.
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Vesta is more massive than Hygiea than Enceladus than Proteus than Mimas. If the criterion is mass rather than actual roundness, your first article is not applying it properly. Not that we know how massive most KBOs are either. 
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“There is no dark side in the moon really. Matter of fact, it’s all dark.”
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