Russell's Blog

Demoting Pluto from "planet" to a "dwarf planet" has got to be one of the dumbest things to happen in science this year. It seems that astronomers will not rest until they have classified every object the see as a dwarf-something. For example, all main-sequence stars, including our own sun, are dwarf stars. This is in addition to other silly conventions, like calling all elements heavier than helium "metals."

I think science is afflicted by a naming-mania. Maybe this is a side effect of biology envy. Biology has names for millions of things; millions of species, hundreds (or maybe thousands) of organs, millions of molecules, and maybe tens of millions of processes. Astronomy, on the other hand, really only has a few clearly distinct objects; rocks, blobs of (somewhat) ionized gas, stars, star corpses, big blobs of stars, big blobs of blobs of stars, and Other. Which particular rocks we call "planets" is an essentially arbitrary choice. At parties, biologists pontificate at length about the peptide sequence of Glycine reuptake receptors they found in the presynaptic ganglia located in the deutocerebrum of the latest and most fashionable breed of knock-out Drosophila melanogaster, and astronomers are forced to string together ordinary words to describe how gas falls onto the surface of a white dwarf. Maybe they feel inadequate that their jargon isn't rich enough, and so they are racing to catch up with biology. Someone ought to slap some sense into them.

Let us meditate on this problem for a moment. Right now, the Moon is a moon. However, it is slowly drifting away from Earth, and will someday escape and begin orbiting the Sun. Then it will "become" a planet. Or, by the time it happens, astronomers would classify it as an under-sub-sub-mini-sub-micro-dwarf planet. But it didn't really "become" anything. It just followed a trajectory. So why change the name? It would really be much neater, and more honest, to adopt a naming convention that recognizes that when we name things that lie on a continuous scale, we make essentially arbitrary demarcations. Take a group of objects that includes rocky things the size of my left upper molar, the size of Manhattan, the size of Madagascar, and the size of Mars. Which things we call "planets" and which things we call "debris" is simply a matter carving up the universe into bins that are convenient for our little anthrocentric minds.

I think someone ought to sue for an injunction against the use of the term "dwarf planet" until an investigation has been conducted to determine how much money the members of the International Astronomical Union will make from the new editions of fifth-grade science textbooks that will surely be required if this change is permitted.