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by Im Alec has abandoned this account on February 17th, 2010
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And so are many thousand asteroids and increasing number of Kuiper Belt Objects. The reason for the demotion was that some Kuiper Belt Objects had been discovered which were larger than Pluto (Sedna, Quaoaar), and every prospect of finding many more. We therefore had a choice: an ever increasing number of planets, all invisible except to the biggest telescopes, or demoting Pluto and being reasonably sure that the list of planets is complete. The latter option was chosen, and all such KBOs, including Pluto, are called planetoids or minor planets.
by Im Alec has abandoned this account on September 10th, 2006
There have recently been a number of discoveries of other things sufficiently like Pluto that, if Pluto is a planet, then they are too.
So the International Astronomical Union had to make a decision. They could have decided:
1. All these other tings are plantes, so the solar system has at least 12 planets, (The usuals, plus Ceres and "Xena"), and expect a crowd more any day now as telescopes get better.
2. Pluto is a planet becasue it always was, for sentimental reasons, and these new ones aren't becasue we say so.
3. Pluto is not a planet, but just another so-called "Kuiper Belt Object" - and then, of course, neither are all the other Johnny Come Latelies.
The rules to be a planet are now:
1. In orbit around a sun.
2. Not a sun itself (i.e. not part of a double star)
3. Big enough to sweep all the debris out of its orbit
Pluto fails test 3, and is demoted.
by FauxLo on February 13th, 2008
What Is a Planet Today?
According to the new definition, a full-fledged planet is an object that orbits the sun and is large enough to have become round due to the force of its own gravity. In addition, a planet has to dominate the neighborhood around its orbit.
Pluto has been demoted because it does not dominate its neighborhood. Charon, its large "moon," is only about half the size of Pluto, while all the true planets are far larger than their moons.
In addition, bodies that dominate their neighborhoods, "sweep up" asteroids, comets, and other debris, clearing a path along their orbits. By contrast, Pluto's orbit is somewhat untidy.
http://news.nationalgeographic.com/news/2006/08/060824-pluto-planet.html
by Norman_Outside the lines on October 5th, 2006
disney characters just arn't as popular as thay once were!!
by Lovely_B on February 13th, 2008
It's not???!
by Time Lord on February 13th, 2008
Because it's too small. If we classed eveything like Pluto as a planet we'd end up with a ridiculous number of planets, all with stupid names like Ub292QW.
by anonymous on September 26th, 2006
Scientisits pick on the small! I mean, yes, it 'doesn't follow the same structure or rotation patterns of the other planets', seeing as it seems it is just a load of ice with an orbit, but it's been considered a planet for years! I'm taking my GCSE's soon, they'll muck it all up! Gits!
by LordPyro on September 10th, 2006
I believe due to its small size, and proximity to other smaller "planets" similar to it ...
by The Reverend Soleil on February 13th, 2008
Because a bunch of scientists got together to try to come up with a more comprehensive list of criteria for what makes a planet, and Pluto didn't qualify.
It's now considered a "dwarf planet", or a Kuiper Belt Object (KBO).
by onzanzabarsands on November 20th, 2006
Because Disney hired him to be Mickey's dog.
by supaballad on February 17th, 2010
Scientists thought it was too small to be a planet. I don't know what kind of moron scientists would waste their time by ruling out universal masses as planets instead of working to better mankind.
by Anonymous on February 17th, 2010
It's just not big enough. Maybe we should use two terms; minor and major planets. A major planet having as much mass as Mercury, for instance. Otherwise, we would have millions of them.
by hong kong phooey on February 17th, 2010
it turns out it`s to small to class as a planet
by billnted on February 17th, 2010
There are millions of solid things that orbit the sun
http://www.tqnyc.org/2006/NYC063368/AsteriodBelt.jpg
It's to so with the objects around its orbit and not having enough mass to clear them. This is the third condition, the other two of which you already mentioned.
by Neko5327 on August 6th, 2009
I don't care what people say :'( I think pluto is a planet!! it's annoying when people change their minds on things over the years! :(
by Paintballstud2.0 on February 17th, 2010
gay! should be a planet
by soomoon on June 8th, 2010
And so are many thousound asteroids and increasing number of Kiper belt objects. the reason for the demotion was that some Kiper Belt objects had been discovered which were larger than pluto (Sedna, Quaoar), and every prospect of finding many more. we therefore had a choice: an ever increasing number of planets, all invisible except to the biggest telescopes, or demotion Pluto and being reasonably sure that the list of planets is complete. the latter option was chosen, and all such KBOs, including Pluto, are called planetoids or minor planets.
by Koloszrodos on July 13th, 2010
There is bigger objects than pluto in the Kuiper belt, but they're not classed as planets because they did not clear their orbits from other space junk, and neither did Pluto, and That's why they were classed as Dwarf Planets, but why should anyone care why is it a planet or not, as long as it's round and has an ecliptic orbit, it doesn't matter if it's a planet or a dwarf planet!
What Is the Average Barometric Pressure of Pluto?
by Answerbag Staff on July 30th, 2009
| 1 person likes this
A tiny, fourth moon orbiting the dwarf planet Pluto has just been discovered. What will we call the newest member of the solar community?
by calicorey on July 24th, 2011
| 1 person likes this
Is pluto still a planet?
by frenzy on November 28th, 2008
| 1 person likes this
Pluto orbits the sun with a period of 247.7 years. What is its average distance from the sun? Please show the math work on how to get this answer.
by Ashley on February 24th, 2009
| 1 person likes this
How far is pluto
by harry1234 on April 2nd, 2011
| 1 person likes this
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Comments
so: "if we call you a planet, then everybody will want to be called a planet"
by purplecows on March 7th, 2010