2007-03-19 00:53:57 · 12 answers · asked by aliengeisha 1 in Science & Mathematics ➔ Astronomy & Space
From its discovery by Clyde Tombaugh in 1930, Pluto was considered the Solar System's ninth planet. In the late 20th and early 21st century, many similar objects were discovered in the outer solar system, most notably the trans-Neptunian object Eris which is slightly larger than Pluto. On August 24, 2006 the IAU defined the term "planet" for the first time. This definition excluded Pluto, which was then reclassified under the new category of dwarf planet along with Eris and Ceres.[6] Pluto is also classified as the prototype of a family of trans-Neptunian objects.[7][8] After the reclassification, Pluto was added to the list of minor planets and given the number 134340.
2007-03-22 01:59:20 · answer #1 · answered by ђermiona 6 · 1⤊ 0⤋
The International Astronomy Union defined the term "planet" scientifically. Pluto does not have the necessary characteristics to be a planet; however it is to big to be an asteroid and has a natural satellite too.
So, Pluto becomes a dwarf planet, along other Trans-Neptunian objects like Eris (another dwarf planet and bigger than Pluto) and Sedna.
2007-03-23 06:44:53 · answer #2 · answered by Tenebra98 3 · 0⤊ 0⤋
pluto is out in an area of the solar system called the kypier belt, this is where there are thousands of object like pluto, so far astronomers have found four other dwarf planets the size of pluto and bigger. so they figured the were going to have to demote pluto or add four more planets, they also assumed they were going to find more of these objects and didnt want to have to keep adding planets to the list. ps. the object that person was talking about named xena, that was just a temporary nickname they have now given it an offical name "eris" hope this helps!!!!!!!
2007-03-19 08:46:00 · answer #3 · answered by Bones 3 · 0⤊ 0⤋
Because Pluto is too small to be a planet anymore.
2007-03-19 08:04:21 · answer #4 · answered by amin_hosni 3 · 1⤊ 0⤋
Because they discover more micro planets like Pluto! So they diminish Pluto! This objects they discovered in Kuiper belt and the astronomers believe that are more like them there! The names of the two objects are Demeter and Xena (yes from the TV series)!
2007-03-19 08:01:03 · answer #5 · answered by filip 4 · 0⤊ 0⤋
According to the definition of a planet, it is supposed to be the only thing in its own orbit. But the orbit of Pluto has some kind of other asteroids and comets in its orbit. thus it is not a planet
2007-03-19 08:56:45 · answer #6 · answered by Anonymous · 0⤊ 0⤋
Being a planet entails certain responsibilities.
By reverting to just a rock the whole solar system is simplified
The efficiency of nature.
2007-03-19 09:17:54 · answer #7 · answered by Billy Butthead 7 · 0⤊ 0⤋
Silly ,everyone knows pluto is Mickey's Dog!!
2007-03-19 07:59:12 · answer #8 · answered by Butch46 4 · 0⤊ 0⤋
It's because i didn't have te features of a planet ( a larger size to begin with)
2007-03-19 08:03:12 · answer #9 · answered by cass 7 · 1⤊ 0⤋
thank the scientists who decided that it's too small after all to be considered a planet.
2007-03-19 08:02:29 · answer #10 · answered by Anonymous · 1⤊ 0⤋