A planet has to be in orbit around the sun. It also has to be more or less spherical in shape, having a high enough mass and therefore gravity to achieve this 'hydrostatic equilibrium'. Thirdly, it has to have cleared it's orbit of most other matter - it has to dominate it's orbit, be the only main body at that particular distance from the sun.
No. Most follow the new IAU definition of a planet which excludes Pluto.
In 2006, pluto's classification was changed to "dwarf planet". This removed it as one of the nine planets in our solar system. It was done so by the IAU (international astronomical union). The main reason for this is due to the orbital path of Pluto as it crosses Neptune's and thus does not fit the IAU's definition of a "planet".
IAU decided this because it shrinks every 10 seconds
The much-debated 2006 reclassification of Pluto as a dwarf planet happened because of the newly agreed-upon threefold definition of a planet: it has to be in solar orbit, has to be spherical (or in hydrostatic equilibrium) and has to have cleared its orbit - and it failed on the third count, since Pluto was considered to have only cleared less than a tenth such mass.
No planet, under the 2006 IAU definition of a planet, takes 557 Earth years to orbit the Sun. Perhaps you are talking about dwarf planets. If so, please restate the question.
No. Most follow the new IAU definition of a planet which excludes Pluto.
The IAU arrived at a new definition for "planet" which left Pluto out in the cold. It is now designated as a "Dwarf Planet".
In 2006, pluto's classification was changed to "dwarf planet". This removed it as one of the nine planets in our solar system. It was done so by the IAU (international astronomical union). The main reason for this is due to the orbital path of Pluto as it crosses Neptune's and thus does not fit the IAU's definition of a "planet".
The IAU arrived at a new definition for "planet" which left Pluto out in the cold. It is now designated as a "Dwarf Planet". also it was called a planet when is was larger but now it has become smaller scientists no longer class it as a planet
IAU decided this because it shrinks every 10 seconds
Planets.Or, if they are smaller and have not met the [http://en.wikipedia.org/wiki/Definition_of_planet IAU definition of a planet], they are called Asteroids.
Ganymede is not a planet because it does not meet the criteria set by the International Astronomical Union (IAU) for planetary status. In particular, Ganymede does not clear its orbital path of other debris, one of the key requirements to be considered a planet under the IAU definition. Instead, it is classified as a moon of Jupiter.
The much-debated 2006 reclassification of Pluto as a dwarf planet happened because of the newly agreed-upon threefold definition of a planet: it has to be in solar orbit, has to be spherical (or in hydrostatic equilibrium) and has to have cleared its orbit - and it failed on the third count, since Pluto was considered to have only cleared less than a tenth such mass.
On August 24, 2006, the International Astronomical Union (IAU) defined the term "planet" for the first time. This definition excluded Pluto as a planet, and added it as a member of the new category "dwarf planet" along with Eris and Ceres.
Yes. The planet was reclassified as a "dwarf planet" by the IAU in 2006.
No planet, under the 2006 IAU definition of a planet, takes 557 Earth years to orbit the Sun. Perhaps you are talking about dwarf planets. If so, please restate the question.
The International Astronomical Union [IAU], classifies Ceres as a Dwarf Planet.