2006-08-28 15:08:26 · 11 answers · asked by Alicia H 1 in Science & Mathematics ➔ Astronomy & Space
a planet must now have it's own orbit,,pluto shares its orbit with another so goodbye planet pluto,they now call it a dwarf planet
2006-08-28 15:13:44 · answer #1 · answered by steve 5 · 3⤊ 0⤋
the international astronomical union defined three new terms "classical planet", "dwarf planet", and "small solar system body".
(1) A classical 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".
mercury, venus, earth, mars, jupiter, saturn, uranus, and neptune are "classical planets". most seem to be unaware of the new term "classical planet".
because pluto orbits the sun, is round, orbits the sun with a bunch of other similar bodies with similar orbits, and is not a satellite it is a dwarf planet. pluto and charon are considered a binary system.
look here:
http://www.iau2006.org/mirror/www.iau.org/iau0602/index.html
2006-08-28 15:28:24 · answer #2 · answered by warm soapy water 5 · 1⤊ 0⤋
Apparently it's not big enough . . . which I think is bullshit . . . it's spherical, orbits the sun (no matter how eccentrically) and its gravity keeps away all small bits of debris like asteroids, to me that's a planet. Even if it was a moon once, it orbits the Sun and not something moving around the sun so it's a planet.
2006-08-28 16:02:15 · answer #3 · answered by Isis-sama 5 · 0⤊ 0⤋
It is a dwarf planet. Not a (full) planet. Because it's too small. At its size, there are 2 other plantery bodies that have the same charateristics (eg. xena) that have to be promoted to planets. Also the orbit plays a part which i believe is not regular orbit cos of its size.
2006-08-28 15:13:28 · answer #4 · answered by madxkatz 2 · 2⤊ 0⤋
The reason is because Pluto has an elongated orbit and crosses into Neptune's.
2006-08-28 15:27:53 · answer #5 · answered by ideaquest 7 · 0⤊ 2⤋
Because the scientist become so stupid, they admit that they do not know how to define the word "PLANET"
2006-08-28 16:19:40 · answer #6 · answered by Answer 4 · 0⤊ 0⤋
Because Walt Disney thought he would make a better cartoon dog.
2006-08-28 15:18:32 · answer #7 · answered by Rudy 3 · 0⤊ 2⤋
1.it's too small to be planet
2.its orbit cut off the Neptune's orbit
2006-08-28 15:17:33 · answer #8 · answered by Anonymous · 0⤊ 2⤋
its not part of our solar system. it doesn't orbit around the sun like all the other planets do. its like just out there.
2006-08-28 15:12:47 · answer #9 · answered by midgit boy 1 · 0⤊ 4⤋
Get over it -- this question is SO OLD.
2006-08-28 15:48:36 · answer #10 · answered by stevewbcanada 6 · 0⤊ 2⤋