The Pluto Debate

The solar system is a regular unit of study in school classrooms. Most kids have had to do a project of some sort on the solar system during our younger school years. The planets in orbit are usually the main focus in basic classes. These projects have taken on a new look with the debate of Pluto’s relevance as a planet. Pluto, however, has changed in the books over the years.  The identity of Pluto has been a discussion among scientists for many years. Numerous variables have contributed to its different roles.

The Planet

Pluto was considered a planet up until 2006. Its discovery in the year 1930 put Pluto on the map of planets. Clyde Tombaugh first noticed Pluto after extensive tests and images.  He declared it a planet. The name of Pluto translates from Latin to “god of the underworld. The defining factor was the orbit around the sun which takes 247.7 years. Known facts about Pluto include incredibly cold temperatures and long days. Temperatures range between -387 degrees Fahrenheit and -369 degrees Fahrenheit. The days average 153.3hours long, about 6 days earth time. Pluto remained a unique existence for some time, enabling it to hold on to the planet label.

The Dwarf Planet

Pluto exists past Neptune and orbits in the Kuiper belt. It was considered the ninth planet, and farthest of all planets from the sun. Pluto remained a planet by scientific standards until further research revealed additional items in the Kuiper belt. Pluto fell into the same category of these objects, also small. These objects became known as the dwarf planets. Pluto was official stripped of the title “planet” in 2006. The debate continues, however, as definitions change.


Part of the debate lies in the inability of scientists to agree on a definition of planet. Varying definitions have been recently proposed. A simple definition of a spherical item out in space would be inclusive of too many other objects, such as moons. There is a need to be more specific. The idea that a planet should not share its orbit excludes Pluto. A student named Kirby Runyon has moved to include only three items in the definition of planet, allowing Pluto back into the game. He states that orbital parameters need not be considered. He also insisted that gravity should be present to help maintain the classic spherical persona. The third requirement insists that the planet should have never experienced nuclear fusion. Until scientists can agree on a stable definition of the word “planet”, Pluto remains in limbo.

Scientific study involves ever changing information. Previous conclusions often meet upheaval when new information becomes available. The label given to Pluto remained in circulation until new discoveries shed light on its lack of proper character. This is, in part, due to its size and similarity to other objects in the Kuiper belt. The debate may be ongoing as new definitions are suggested. The understanding of Pluto that many of us grew up with may be a thing of the past.


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