|Pluto Loses Planetary Status
Recent discoveries of large objects orbiting the Sun beyond Neptune and Pluto have prompted the International Astronomical Union (IAU) to re-examine the way planetary bodies are classified. On August 24, 2006, the IAU passed a resolution redefining the criteria for planetary status. A planet is defined by three properties.
1) It is a celestial body that orbits the Sun.
Under this definition, our Solar System has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Because Pluto resides in an area of space populated by numerous other objects, it is no longer considered a planet. Pluto is now designated a dwarf planet, and it is the prototype of a class of objects located beyond the orbit of Neptune.
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