What 8 The Last Planet : Why is pluto no longer a planet ? Because My very Excellent Man just sent us Nine !
why is pluto no longer a planet ?
In 2006, the International Astronomical Union (IAU) updated its definition of a planet, which resulted in Pluto being reclassified as a dwarf planet. The new definition of a planet requires that an object orbiting the Sun must meet all of the following criteria:
It must be in orbit around the Sun.
It must have sufficient mass to be rounded by its own gravity.
It must have “cleared the neighborhood” around its orbit.
Pluto meets the first two criteria, but it does not meet the third. Pluto’s orbit overlaps with the Kuiper Belt, a region of the solar system that contains many other icy bodies. This means that Pluto has not “cleared the neighborhood” around its orbit, and therefore it does not meet the IAU’s definition of a planet.
The IAU’s decision to reclassify Pluto was controversial at the time, and there is still some debate about whether or not it was the right decision. Some scientists argue that the new definition of a planet is too restrictive, and that Pluto should still be considered a planet. Others argue that the new definition is necessary to make the classification of planets more clear and consistent.
Despite being reclassified as a dwarf planet, Pluto is still a fascinating object. It is the largest dwarf planet in the solar system, and it has a complex and unusual orbit. Pluto is also home to five moons, one of which is about half the size of Pluto itself.
So, while Pluto may no longer be considered a planet, it is still a very interesting and important part of our solar system.
The very excellent man’s statement about “Nine planets” is technically inaccurate according to the current definition of a planet adopted by the International Astronomical Union (IAU) in 2006. The IAU’s definition requires that a planet must “clear the neighborhood” around its orbit, which means it must have eliminated most of the other objects in its orbit. Pluto, however, shares its orbit with many other icy bodies in the Kuiper Belt, so it does not meet this criterion. As a result, Pluto was reclassified as a dwarf planet in 2006.
Therefore, there are currently only eight planets recognized by the IAU: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto is one of the five largest dwarf planets in the solar system, along with Ceres, Eris, Makemake, and Haumea.
