User:Rursus/Pluto

Why did the few astronomers at IAU make a bad job of defining planet and dwarf planet? Because they disregarded the rules of the English language, and disregarded a lot of other astronomers' former use of the word planet.

What the IAU decision partakers (according to rumor, a group of angry planet dynamicists intent on making a power demonstration) did wrong was:

• claiming that dwarf means having cleaned up its own orbit by a committee decision;

• claiming that a dwarf-something is not a something – normally we speak about dwarf elephants being elephants, dwarf stars being stars, dwarf crocodyles being crocodyles – but the IAU decision partakers deliberately claimed that dwarf planets aren't planets, explaining that since minor planets aren't planets, they had the right to emulate a misnomer that emerged evolutionary by initial misconceptions; so that little IAU decision partaker clique decided to disregard the whole area of linguistics, by a committee decision;

• defining planets to be bodies going in orbit around Sun, nothing else; OK, so what about those exoplanets? Disregard! OK, so what about those rogue planets? Disregard! Like kings doing grandious gestures while the lowly rabble admires? No, not at all.

My conclusion: IAU cannot be trusted with such linguistic kind of questions – the members don't have the philosophical insight to understand that the long-term success of their science, is grounded in their ability to communicate with other scientists, and the public who pays their funds. The IAU definition of planet is nil, illegal, void, rubbish, nonsense. I'll use the term "dwarf planet" (bouahahaha!) only in order to lead people away from its usage.

(Whytheh*c did I write this here?? This is an encyclopedia)

Lol, the way I see it, if the dang thing is round and doesn't have nuclear fusion then it's a planet. But it's hard not to think of Titan or Ganymede as moons, or Ceres as an asteroid, or Eris as a KBO though. We're too used to thinking this way. These terms are overlapping subsets of "planet", some examples are large enough to be planets even though most of them aren't. I'd say a brown dwarf is not a planet though, since if fuses deuterium. Sagittarian Milky Way 22:16, 30 March 2007 (UTC)

Hi Sagittarian Milky Way! I share that opinion, approximately, except that by my opinion, a planet is or was melted/differentiated inside. That makes Titan and Ganymedes planets, and probably Ceres and Vesta, but that's about the lower bounds. I think, when IAUers speak of "planets", they mean what I would refer to as "regular (orbit) planets". This d*rnd conscious misnomer "dwarf planet" of theirs, refers to "irregular planets". In my opinion, a moon may also be a planet, but since it is not in an orbit aroun the Sun, a moon is never a regular planet, neither would Pluto nor Eris be properly classified as regular. Said: Rursus 11:10, 19 April 2007 (UTC)

This user is not a member of IAU, and would rather cut his/her right arm than ever be!

for the inner circuit! Said: Rursus 15:06, 19 April 2007 (UTC)

Right, there's good old regular planet, and then there's "others". This kindof makes it obvious: List of solar system objects by planetary discriminant

Informative link. Then "dwarf planet" only lacks the linguistics wellformedness. Let's say "non-regular", but using the Soter Term, in what group falls the icy equipotential moons? "Dwarf planets"? Said: Rursus 17:36, 11 May 2007 (UTC)

Moons and objects in resonance aren't counted against the body in question. You could do an analogous thing with each planet to seperate its major moons from the minor moons say, they might need to find all the really tiny moonlets though to make an accurate determination.

I wonder what the definition of 'the orbit it has to clear' is exactly. Is it the body's Hill Sphere drawn out into a torus? Sagittarian Milky Way 02:32, 20 May 2007 (UTC)

A moon can never be a regular planet cause it's a moon. Doi. Like the forest moon of Endor, which must be around the size of Earth.

In comparative planetology you don't have to give a care about where it is and what it does, so they're like 57 round bodies or something. That's where you get the nice graphs of all the stuff like mass vs density. With the dots colored by iciness vs rockiness, and they put a slanted line for the limit of roundness. I saw that in Sky & Telescope once. So it's remarkable that there's like a line, and Mimas is barely above that line, it's the smallest planet, and something like Pallas which is almost twice the size might not be a planet because Pallas has no ice and so is harder to squeeze. The limit of roundness is sharper once density is taken into account.

Flawed

I really think that the definition of a planet that got passed is beyond flawed. 1) It has to be orbiting the SUN, and not any other star. 2) The cleared its neighborhood bit is a "bit" lacking in clarity. As I understand it the previous week's attempted definition from the conference had been forwarded by Planetary Geologists, but they'd been butting heads with the Orbital Dynamicists who basically pulled a coup on the very last day after the great bulk of the Planetary Geologists had gone home. A moon is a moon regardless of size as long as it is also orbiting something other than a star. In my book if it is primarily orbiting a star; has a mass and/or size on par with Pluto (I know, maybe a bit to arbitrary, but I'm working on a better qualifier), or more massive/larger; it really shouldn't matter if its orbit is seriously inclined, or if its orbit is highly elliptical. When you have planets like Jupiter or larger that can potentially fling Earth sized planets into strange orbits I really think that the types of orbits objects are in have less to do with planethood than size. With the planets (I'll call them this even though they're not going around the Sun) that are being found around other stars we're finding a pretty large number of things Jupiter-sized in Mercury-type orbits, which seems to indicate that even Gas Giant planets can migrate from where they initially formed, so it seems to me that orbital characteristics should have very little to do with planethood. Phil 06:20, 16 June 2007 (UTC)

Yes, flawed! Actually the question of planethood is neither astronomical, nor administrative, nor political, but a linguistical and philosophical problem, which should be regarded as a long time planning for avoiding unnecessary genre-conflicts within science, and splitup in non-communicating science branches. Many astronomers say they don't care about these kinds of definitions, because they already know what they're speaking about, but I wonder what will happen when they run out of three letter abbreviations. SSSB? Four or five and people start to become confused... Astronomers that wish to simplify future astronomical communication, need to base a new definition on all previous usages, but make some rationalization as to involve as few and as clear criteria as possible to the new definition. Otherwise we get ten Three-letter abbreviation when we need two terms something like meteoroid, methaniceoid or some such. Said: Rursus ☺ ★ 20:47, 27 June 2007 (UTC)