People are saying that it's not really a planet.The definition of 'planet' is a round object in space that revolves around a star that does not sustain itself with nuclear fusion.And Pluto qualifies.So why do they say it's not a planet?
2006-09-19 17:29:09 · 14 answers · asked by mexicananime06 1 in Science & Mathematics ➔ Astronomy & Space
(1) A "planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit.
(2) A "dwarf planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) has not cleared the neighborhood around its orbit, and (d) is not a satellite.
(3) All other objects orbiting the Sun shall be referred to collectively as "small solar system bodies".
http://www.iau.org/fileadmin/content/pdfs/Resolution_GA26-5-6.pdf
pluto is not a planet, but pluto orbits the sun, is round, does not have an isolated orbit (a bunch of other similar bodies have similar orbits.), and is not a satellite so it is a dwarf planet. this does not change anything about the solar system or pluto. it just corrects the mistake of classifying pluto as a planet initially.
this same thing has happened before. beginning in 1800, astronomers found a few bodies orbiting between the orbits of mars and jupiter, and they finally stopped calling them planets after the fourth discovery. 150 years from now, no one will think of "134340 pluto" as a planet. very few will even know we classified it as a planet. "1 ceres" and "136199 eris" are other dwarf planets.
i have been waiting for this since i was about twelve. i feel somewhat satisfied. i knew that pluto didn't fit the pattern set by the major bodies in the solar system so it was an anomaly. it just felt illogical and "out of place". this was the right thing to do, believe me. i don't understand why so many are having such a problem with this.
i don't know how long this will drag on tho. many planetary scientists are not satisfied that the definition is rigorous enough.
http://en.wikipedia.org/wiki/Pluto
2006-09-20 06:17:23 · answer #1 · answered by warm soapy water 5 · 3⤊ 0⤋
They had to reclassify it, or there'd be 20 or 30 more planets in a few years. They are finding that there are 100's of objects outside of Neptune's orbit, some smaller than Pluto, some larger that Pluto.
There has always been some debate about Pluto in it's major planet status. It's orbit is a different shape and it's on a different plane than the rest of our system. (I learned this in school too)
It's still out there, people need to chill out. Open your brains, learn more about our solar system.
2006-09-19 18:30:51 · answer #2 · answered by biggie 5 · 1⤊ 0⤋
Pluto's orbit takes it near a significant number of other similar objects called Kuiper Belt objects, or KBO's. Simply put, it's not the biggest thing in its vicinity, so it's a dwarf planet.
2006-09-19 18:36:16 · answer #3 · answered by Joseph Q 2 · 1⤊ 0⤋
the matter of pluto to be not a planet was launched after some new rules given by the scientists about a planet... it is that one planets orbit should not interface others and its orbit must be a circle..
since pluto goes in a elliptical orbit around the sun and it interfaces the Neptune's orbit it was said to be not a planet any more it belongs to the next category....
is your dough ts clear......
2006-09-19 17:41:07 · answer #4 · answered by achu 2 · 0⤊ 2⤋
Because it was the definition of Planet the one they changed, so it does not qualify any more as a planet. I was bumped too.
2006-09-19 17:34:42 · answer #5 · answered by Martisa 3 · 0⤊ 1⤋
When I was in school, Pluto was a planet.
I'll always think of it as a planet.
The reason why they say it doesn't qualify is because it's quote-on-quote "too small".
2006-09-19 17:38:32 · answer #6 · answered by peddlersofdeth 2 · 0⤊ 2⤋
You missed out one thing: It does'nt clear the neighbourhood around it's orbit.
2006-09-20 01:23:50 · answer #7 · answered by Eddy G 2 · 1⤊ 0⤋
Well now it's a dwarf planet so yeah
2006-09-19 18:01:53 · answer #8 · answered by Anonymous · 0⤊ 1⤋
It's a planet, but only a dwarf one.
Sorry, I don't make the rules.
2006-09-19 17:37:43 · answer #9 · answered by Lost. at. Sea. 7 · 0⤊ 1⤋
They say that it isn't a _planet_ because it is now classified as a _dwarf planet_. Which is kinda stupid, neh?
2006-09-19 17:32:25 · answer #10 · answered by mattomynameo 4 · 0⤊ 2⤋