The following is a followup by John Vester addressing responses to his original article published in Analog, titled "Pluto: Planet or Not."
Since the time the essay was published in Analog magazine, other than a few friends telling me they thought it made sense, I have received some pointed critiques of the science.
I also received some links to relevant scientific papers:
1) A Geophysical Planet Definition
https://www.hou.usra.edu/meetings/lpsc2017/pdf/1448.pdf
2) Reductionist vs. Folk Taxonomies in Planetary Science
www.hou.usra.edu/meetings/lpsc2021/pdf/1083.pdf
3) An Organically Grown Planet Definition
https://astronomy.com/magazine/2018/05/an-organically-grown-planet-definition
4) Ignore the IAU! Dwarf Planets are Planets Too
https://www.youtube.com/watch?v=m-WsYl_wWNo
Five main objections to my Linguistic Planetary Definition have come to my attention.
The proposed linguistic definition lacks simplicity because some objects that would be considered planets by this scheme can become captured into orbit around another object, making it now a moon by my scheme.
ANSWER – This objection is a defense of the misguided attempt, on both sides, to infuse the definition of the word “planet” with too much baggage in support of the astronomer’s or the planetary scientist’s preferences.
The essence of the linguistic definition is simplicity. A planet is simply anything that orbits a star. If some object changes from one category to another, it should not be a problem. When a tadpole changes to a frog, or a caterpillar into a butterfly, there is no confusion. So if a rock changes from being an asteroid to being a moon, it should not be upsetting. It happens at the subcategory level without complaint. An asteroid sometimes comes back to life, as it were, and is treated as and called a comet.
My “Power to the people!” line drew some ire. It’s up to science, I am told, to raise the public’s understanding of nature. The public did not accept the notion of Earth as a planet, but Copernicus and science prevailed, even though the public was wrong. We shouldn’t be dumbing down scientific terminology to satisfy the views of the public.
ANSWER – Setting aside the fact that the Copernican revolution was a revolution in understanding, not a revolution in nomenclature, the linguistic approach does reclaim some words for the language, allowing science full rein over all the subcategories.
The overarching categories, like planet, moon, and star, ought to be based on simple, discriminating principles, such as what it orbits, or whether it has achieved nuclear fusion in its core. To burden the word “Planet” with questions of shape, geologic activity, clearing of orbits, etc. serves no purpose in helping educate the public. These confusing stipulations may please the scientists on those teams, but will only result in the division and the gnashing of teeth, as we see now regarding Pluto.
I have been accused of including hearsay by relating the story of “snow” and the languages of the Eskimos/Inuits.
ANSWER – While I included the words “It is said” in an attempt to make it clear that I make no claim as to the truth of the story, it does illustrate an important point. As one becomes more intimately involved with something, clarity of communication demands more precise language about it.
As we enter a golden age of astronomy, thanks to incredible probes, like New Horizons, and fantastic telescopes, like JWST, and which we will continue to launch, and as findings, news, and discussions of mission discoveries continue to proliferate, we need to clarify out terminology.
The scientific community is in a similar position to what Zoology was like in the 1700s. What we need is a modern day Carl Linaeus to develop a taxonomy for space objects. But the overarching category names should not be discarded. In spite of Linaeus, we still talk about horses and dogs. And we still observe that there are plant, animal and mineral kingdoms. How is star, planet and moon different?
Fault has been found with my statement that originally all planets were mere specs of light in the night sky. On the contrary, the sun and moon are held up as proof.
ANSWER – This proves nothing. Back then, as now, the sun and moon are not, neither of them, planets. The GPD folks are eager to start calling large moons planets, which seems to me a step in the wrong direction.
I have been taken to task for ignoring or missing “one of the greatest insights in scientific history,” which is that space objects large enough to be complex and, as Galileo put it, to be homes for life and civilizations, are planets. During the 1700s and 1800s, science dropped the “homes for life and civilizations” part, but they kept the size and complexity part. This important central insight is a central part of the GPD argument.
ANSWER – Let’s notice that science gets it wrong too. Galileo’s speculations about life and civilizations were dropped so as to keep lifeless planets in the planet club. Note too that the GPD would have us referring to our moon, and others, as planets because they show evidence of geologic activity. How confusing compared to simply referring to what something orbits, or compared to what we have seen and heard in hundreds of years of literature and song.
Let things like size and shape and complexity be handled in research and at the subcategory level. If the GPD wants Luna (or Titan, or Enceladus, etc.)to be planets, what happens if the supposed geologic activity completely ceases? And what if it starts up again? The chance exists that this will happen at some point and require new GPD designations. But that’s the crux of Objection #1!
With all that said, it occurred to me that there is a sort of grey area that should be appreciated.
My proposal is from a spoken language stand point. Objections to these ideas comes from a science stand point. While science may feel an obligation to reach down and educate the public on what science has learned about how the world works, I resist the notion that science always knows best.
We, the people, should lay claim to some basic words, like star, planet and moon. If we do not, science can make a mess of things, as they did with the word “metal.” In common parlance we know what metals are. Hard, shiny, bendy. Good enough for everyday use. Chemistry has expanded on the definition to mean any element or alloy that handles electrons in certain ways. Useful and interesting. But the Astrophysicists use the word to man any element in the periodic table heavier that hydrogen or helium. How is this helpful in educating the public?
In conclusion, the overarching categories, “star,” “planet,” and “moon,” should be the province of the man on the street, with simple, easy to understand criteria. All the many subcategories should be the province of science.