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Some fascinating resolutions were made at this years'
IAU (international astronomical union) General Assembly 2006 Meeting
One that has caught our attention recently: definition of a "planet". Pluto is not amoung them. (instead it is placed in a new category: "dwarf planet" )
IAU (international astronomical union) General Assembly 2006 Meeting
One that has caught our attention recently: definition of a "planet". Pluto is not amoung them. (instead it is placed in a new category: "dwarf planet" )
RESOLUTION 5A
The IAU therefore resolves that "planets" and other bodies in our Solar System be defined into three distinct categories in the following way:
(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 neighbourhood 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 neighbourhood around its orbit, and (d) is not a satellite.
(3) All other objects except satellites orbiting the Sun shall be referred to collectively as "Small Solar-System Bodies".
1-The eight planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
2-An IAU process will be established to assign borderline objects into either dwarf planet and other categories.
3-These currently include most of the Solar System asteroids, most Trans-Neptunian Objects (TNOs), comets, and other small bodies.IAU Resolution: Pluto
RESOLUTION 6A
The IAU further resolves:
Pluto is a "dwarf planet" by the above definition and is recognized as the prototype of a new category of trans-Neptunian objects.
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