how come pluto isnt a planet anymore?
2006-09-02 06:16:43 · 10 answers · asked by Daniel C 3 in Science & Mathematics ➔ Astronomy & Space
the international astronomical union defined three terms "planet", "dwarf planet", and "small solar system body". this does not change anything about the solar system or pluto. it just corrects the mistake of classifying pluto as a planet initially.
i have known since i was about twelve that pluto does not have the physical and orbital characteristics that fit the pattern set by the major bodies in the solar system, and later, after the discovery of hundreds of other similar bodies with similar orbits, i knew this was inevitable. this was the right thing to do, believe me.
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.
(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".
look here:
http://www.iau2006.org/mirror/www.iau.org/iau0603/index.html
2006-09-02 06:32:22 · answer #1 · answered by warm soapy water 5 · 2⤊ 0⤋
PLuto is too small compare to the satellite of Moon or the planet of Mercury. PLuto is considered ad a asteroid like Ceres.
Also, its orbit turn in a strange way compare to othes planet and even surpass or closely collide the orbit of Neptune.
Since Pluto is not a planet anymore, it is now a asteroid who have the same role as planets but very small diameter and mass.
2006-09-02 15:16:34 · answer #2 · answered by Ritsuko 2 · 0⤊ 1⤋
Because it has an eccentric orbit and is too small. Astronomers are only recently devising criteria as to what makes a heavenly body a planet, as opposed to a planetoid (what they are now calling minor planets). Neither Pluto nor Chiron fit these new criteria (both are too small, and Pluto's orbit crosses Neptune's).
2006-09-02 13:24:13 · answer #3 · answered by yossarius 4 · 0⤊ 1⤋
Because if they let it be a planet, there would be at least 4 other bodies that would have to be planets including Pluto's own moon.
2006-09-02 13:22:44 · answer #4 · answered by Anonymous · 0⤊ 2⤋
something about it is no bigger than an asteroid or a comet and it only circles the sun once like in so many gazillion years and it is just like a block of ice so yeah that is why it is not a planet. that is what i heard on gma!!! does this answer your question???
2006-09-02 13:29:33 · answer #5 · answered by jsk_dlp2004 1 · 0⤊ 1⤋
Because 3,000,000,000,000,000,000 people have asked this question here already. Bit behind on the news, aren't you?
2006-09-02 13:23:01 · answer #6 · answered by stevewbcanada 6 · 0⤊ 1⤋
I think they just found out that it is just a big ball of ice or something
2006-09-02 13:23:27 · answer #7 · answered by Anonymous · 0⤊ 1⤋
Because it's orbit coincides with that of neptune.
2006-09-02 13:37:41 · answer #8 · answered by Samvit 1 · 0⤊ 1⤋
It's too small.
2006-09-02 13:22:20 · answer #9 · answered by midlandsharon 5 · 0⤊ 2⤋
its too tiny
2006-09-02 13:22:49 · answer #10 · answered by aceyacey 2 · 0⤊ 2⤋