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A New Definition Would Add 102 Planets To Our Solar System -- Including Pluto (washingtonpost.com)
The Grim Reefer quotes a report from The Washington Post: Is Pluto a planet? It's not a question scientists ask in polite company. "It's like religion and politics," said Kirby Runyon, a planetary scientist at Johns Hopkins University. "People get worked up over it. I've gotten worked up over it." For years, astronomers, planetary scientists and other space researchers have fought about what to call the small, icy world at the edge of our solar system. Is it a planet, as scientists believed for nearly seven decades? Or must a planet be something bigger, something more dominant, as was decided by vote at the International Astronomical Union (IAU) in 2006? The issue can bring conversations to a screeching halt, or turn them into shouting matches. "Sometimes," Runyon said, "it's just easier not to bring it up." But Runyon will ignore his own advice this week when he attends the annual Lunar and Planetary Science Conference in Houston. In a giant exhibit hall crowded with his colleagues, he's attempting to reignite the debate about Pluto's status with an audacious new definition for planet -- one that includes not just Pluto, but several of its neighbors, objects in the asteroid belt, and a number of moons. By his count, 102 new planets could be added to our solar system under the new criteria. USA Today reports: "In the mind of the public, the word 'planet' carries a significance lacking in other words used to describe planetary bodies," the proposal states. "In the decade following the supposed 'demotion' of Pluto by the International Astronomical Union, many members of the public, in our experience, assume that alleged 'non-planets' cease to be interesting enough to warrant scientific exploration."
Well, then, it's time to start teaching that there's only 8 rivers in the world, and all others are dwarf rivers and don't count as rivers. And 8 bones in the human body, the rest being dwarf bones that aren't really bones. And 8 particles in physics, and all others dwarf particles and don't count as particles. And 8 galaxies in the universe.... you get the picture.
Since we're apparently going into shouting mode, Pluto IS FAR MORE LIKE THE TERRESTRIAL PLANETS THAN THE TERRESTRIAL PLANETS ARE LIKE THE GAS GIANTS. If anything should be kicked out of the planet club, it's the gas giants.
The issue isn't whether KBOs should have their own classification. They do: KBOs. The question is whether it makes sense to group dissimilar objects (terrestrial planets and gas giants) but artificially exclude other objects in hydrostatic equilibrium, objects with active geology, internal differentiation, fluids, and all of the other hallmarks we associate with planets. Nature has given us a very clear dividing line: objects in hydrostatic equilibrium are where you go to see tectonics, mineralization, fluids, search for life, etc, while objects not in hydrostatic equilibrium are where you go to learn about the formation of the solar system, find its building blocks, learn about what life was built from, etc. Nature rarely gives us such meaningful dividing lines, but in this case, it has, and we should respect it.
Aeris Died For Your Sins.