why pluto is not a planet?

Question

what need to be a planet

Answer 1

The IAU members gathered at the 2006 General Assembly agreed that a "planet" is defined as 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 neighbourhood around its orbit.

This means that the Solar System consists of eight "planets" Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. A new distinct class of objects called "dwarf planets" was also decided. It was agreed that "planets" and "dwarf planets" are two distinct classes of objects. The first members of the "dwarf planet" category are Ceres, Pluto and 2003 UB313 (temporary name). More "dwarf planets" are expected to be announced by the IAU in the coming months and years.

Aloha

Answer 2

According to the new definition, a full-fledged planet is an object that orbits the sun and is large enough to have become round due to the force of its own gravity. In addition, a planet has to dominate the neighborhood around its orbit.

Pluto has been demoted because it does not dominate its neighborhood. Charon, its large "moon," is only about half the size of Pluto, while all the true planets are far larger than their moons.

In addition, bodies that dominate their neighborhoods, "sweep up" asteroids, comets, and other debris, clearing a path along their orbits. By contrast, Pluto's orbit is somewhat untidy.

Answer 3

pluto is not a planet coz a planet has the gravity to 'sweep' the universe as it revolves around the sun. this means that as solid matter like small meteorite stones and other stuff that just float around in space are attracted or pulled to the gravitational planet. unfortunately, pluto doesn't pull those kinds of things toward it so it can't be considered a planet. it is instead known as a 'dwarf planet' although there is still debate on whether a dwarf planet is still a planet just as a notebook is still a book.

Answer 4

Pluto was first discovered by astronomer Clyde Tombaugh in 1930 through
multiple observations of the planetary system. Advances in telescope
technology and further discoveries of planetary bodies in the 21st century
started the debate on the status of Pluto as a planet. The IAU on 24 Aug 06
decided to adopt a set of new rules for a planet: "a celestial body that is
in orbit around the sun, has sufficient mass for its self-gravity to
overcome rigid body forces so that it assumes a nearly round shape, and has
cleared the neighbourhood around its orbit." In essence, the oblong orbit
of Pluto that goes into Neptune’s elliptical orbital path disqualifies
Pluto as one of the planets in the solar system.

You may find the following information on Pluto useful:

1. International Astronomical Union and the resolution on the definition
of a planet
http://www.iau.org/
http://www.iau2006.org/mirror/www.iau.org/iau0603/index.html

2. Pluto gets the boot:
http://www.cnn.com/2006/TECH/space/08/24/pluto.ap/index.html

3. It's official--Pluto's out
http://news.com.com/Images+Its+official--Plutos+out/2300-11397_3-6106240.html?tag=st.bp.story


4. Information about Pluto
http://en.wikipedia.org/wiki/Pluto

5. Clyde Tombaugh
http://en.wikipedia.org/wiki/Clyde_Tombaugh

Answer 5

Officially isn't because a planet has the following properties.
1. It revolves around a star
2. It is large enough to look spherical.
3. It clears other objects in it's orbit.

Pluto doesn't do #3. Because it's orbit crosses Neptune. Now you might ask. Why is Neptune still a planet?

Answer 6

because Pluto is to small to be considered a planet and also a planet has to have its own orbit path, not crossing into another planets orbit path, Pluto, i believe crosses paths with Neptune (someone correct me if i am wrong)

Answer 7

Because those stupid scinetist think just becase it is a small planet they call it a dwarf planet and not call it a planet. That's like telling the guy that played mini-me that he's not a Human because he is a Small person or Dwarf.

Answer 8

i don't know but ill take a whack at it i think it is because it it way to small and it crosses paths with neptune unlike all the other planets that don't that

Answer 9

had to be an orbiting object and it had to have sufficient gravity to clear out its orbit of other objects. Neptune does not meet this criteria - but was allowed in based upon a footnote.

Answer 10

it has nothing to do with size. msn.com's article was saying it's no longer a planet bec. it takes over 200 years to circle the sun one time. I would check it out on www.msn.com if you want more info on the subject.