2006-10-06 21:21:38 · 16 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
Because Pluto is an odd planet. It's orbital plane is tilted so crazily that it cannot be considered one of the mainline planets. It's moon is 50% its size, and they orbit in such a way that the center of their mass is not in either planet.
Further, Pluto was the first of many Kuiper Belt objects to be discovered. The KB is a cloud of comets, planeteismals, and other space debris far outside the solar system. It is believd that Pluto was pulled in by the gravity of the sun, and is one of the largest KB objects. Because it is one many similar objcets, it is undeserving of the title of "planet;" whereas the otherplanets are unique due to their size and composition.
2006-10-06 21:30:04 · answer #1 · answered by D-Money 2 · 1⤊ 2⤋
maybe, what you are looking for may be found here:
http://en.wikipedia.org/wiki/Pluto
pluto does orbit the sun, is ball-shaped, does not have an isolated orbit (a bunch of other similar bodies have similar orbits.), and is not a satellite so it is not a planet. this does not change anything about the solar system or pluto. it just corrects the mistake of classifying pluto as a planet initially. i don't know how long this will drag on tho. many planetary astronomers are not satisfied that the definition is rigorous enuf. i can accept that the definition is flawed, but i can not accept that pluto is a planet.
many astronomers consider pluto and charon to be a binary system, but two small bodies orbit that system. they are called nix and hydra.
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 "out of place". now that astronomers have found hundreds of other bodies with similar orbits, classifying "134340 pluto" as a planet is even more irrational. this was the right thing to do, believe me.
incidental, "134340 pluto" was never a moon of neptune. neptune did capture triton. this is why triton has a retrograde orbit.
2006-10-07 12:41:15 · answer #2 · answered by warm soapy water 5 · 0⤊ 0⤋
A planet has some physical properties that are different from other moving objects in the space. Pluto has only one property of those three propertires/characterstics of the planets. the three characterstics of planets are:
1.) it should rotate on a fixed axis, in a fixed time period and in a relevent manner.
2.) it should clear its surroundings, i.e. it should not have other space objects arround it.
3.) A planet should have a hard, rigid surface.
Pluto has one one property i.e. it has a fixed axis and orbit but has not cleared its surroundings, it has many other small objects surrounding in its neighbour. Pluto also does not have a rigid body, it has a smooth cloudy surface.
so by study it has shown that it has only one characterstic of three so it should be called half planet or a Planetoid.
2006-10-07 05:12:28 · answer #3 · answered by Ayaz Ali 4 · 0⤊ 1⤋
there are many good reasons why pluto is not a planet.
- pluto is tiny
- pluto's orbit is not circular like the other planets
- pluto's plane of orbit is far different than that of the other planets (it's off by like 15 degrees from that of earth)...
- there are objects further out from pluto that are actually larger but are not considered planets
- there are asteroids (like Ceres) that are almost as big as pluto
- Pluto and its moon are actually orbiting each other, rather than the moon orbiting pluto...
- pluto is just too different from the other 8 planets to be in the same classification as them...
pluto is a dwarf planet... i think that is a good term for objects the size of pluto.
2006-10-07 04:34:41 · answer #4 · answered by Brooks B 3 · 0⤊ 2⤋
we know that to be planet there should be 3 reason.1st reason was that it should have its gravitational force,2nd was it should revolve on sun and 3rd was it should have it's own fixed orbit.pluto fulfills 1st and 2nd reason but it didn't fulfills 3rd reason because it some time revolve on Saturn's orbit.
its was reason why pluto was not taken as planet.
2006-10-07 07:28:01 · answer #5 · answered by surendra 1 · 0⤊ 1⤋
Man I know how you feel Pluto was my favorite planet.
2006-10-07 04:24:42 · answer #6 · answered by Heavy Metal 3 · 1⤊ 3⤋
cant u just go on yahoo news and type in pluto not a planet?
!!
2006-10-07 04:22:44 · answer #7 · answered by Anonymous · 1⤊ 2⤋
Another so far unmentioned reason is that pluto is almost entirely made of ice-if it were say, Earth's distance from the sun, it would melt, and "grow" a "tail" just like a comet.
2006-10-07 06:13:18 · answer #8 · answered by heavenlybawdy 1 · 0⤊ 2⤋
It does not fit into the criteria of a planet anymore.
2006-10-07 04:23:04 · answer #9 · answered by Dr Dee 7 · 1⤊ 1⤋
Because they don't consider it to be large enough to be a planet so it now called a "Dwarf"
2006-10-07 11:56:16 · answer #10 · answered by Mailman Bob 5 · 0⤊ 1⤋