How Many Planets Have The Solar System?
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Publicado: 15 de julio de 2012
How many planets have the solar system?
Traditionally, since the discovery of Pluto, we considered that the solar system was formed by 9 planets. Butit seems that this is not so clear and the definition of what a planet has recently been questioned. During the month of August 2006 have proposed newdefinitions were the number of planets range from 8-12.
Finally, on August 24, 2006 at the XXVI Assembly of the International Astronomical Union (IAU) hasvoted a new definition of planet, establishing three categories of objects orbiting the Sun
First class. "A planet is a celestial body that is in orbitaround the Sun, which has enough mass to have self-gravity to overcome rigid forces of a body so that it assumes a hydrostatic balanced and that hascleared near its orbit. "
In this category are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Second category. "A dwarf planet is acelestial body orbiting around the Sun, which has enough mass to have self-gravity to overcome rigid forces of a body so that it assumes a hydrostaticbalanced that has not cleared the vicinity of its orbit and is not a satellite. "
This category include Pluto, Xena, and Ceres.
Third category. "All otherobjects orbiting the Sun are considered 'small bodies of the Solar System."
In this category are asteroids and comets.
The result is that the solarsystem happens to have only 8 major planets and Pluto is demoted to the second category.
http://www.mallorcaweb.net/masm/Planetas/nuevosplanetas.jpg
Traditionally, since the discovery of Pluto, we considered that the solar system was formed by 9 planets. Butit seems that this is not so clear and the definition of what a planet has recently been questioned. During the month of August 2006 have proposed newdefinitions were the number of planets range from 8-12.
Finally, on August 24, 2006 at the XXVI Assembly of the International Astronomical Union (IAU) hasvoted a new definition of planet, establishing three categories of objects orbiting the Sun
First class. "A planet is a celestial body that is in orbitaround the Sun, which has enough mass to have self-gravity to overcome rigid forces of a body so that it assumes a hydrostatic balanced and that hascleared near its orbit. "
In this category are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Second category. "A dwarf planet is acelestial body orbiting around the Sun, which has enough mass to have self-gravity to overcome rigid forces of a body so that it assumes a hydrostaticbalanced that has not cleared the vicinity of its orbit and is not a satellite. "
This category include Pluto, Xena, and Ceres.
Third category. "All otherobjects orbiting the Sun are considered 'small bodies of the Solar System."
In this category are asteroids and comets.
The result is that the solarsystem happens to have only 8 major planets and Pluto is demoted to the second category.
http://www.mallorcaweb.net/masm/Planetas/nuevosplanetas.jpg
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