“I was teaching the day it got zapped”, said earth science teacher Mr. White, “I hate to say it but it’s a dwarf planet”.  Pluto became the ninth planet in the solar system in 1930 and it held this title for almost 76 years until August of 2006.  The International Astronomical Union, a worldwide association of astronomers, demoted the planet because it no longer fit the qualifications.   According to NASA one way those scientists define a planet is as a “natural object in space that is massive enough for gravity to make it approximately spherical”.  Now , there are many objections concerning this general definition because some scientist don’t agree that it explains enough, such as how round must the object be to gain the title “planet”? 

This is exactly why Alan Stern, a principle investigator in NASA’s New Horizons mission to Pluto, along with some colleagues, proposed a new definition for the term “planet”.   The New Horizons mission to Pluto is where a spacecraft only the size of a piano launched in January of 2006 to observe and photograph Pluto.  In the summer of 2015, the spacecraft finally passed Pluto and its five moons gaining an abundant amount of new information.  So to counteract the title change of Pluto, Stern and his colleagues crafted their own definition of a planet in their proposals which is “a sub-stellar mass body that has never undergone nuclear fusion and that has sufficient self-gravitation to assume a spheroidal shape adequately described by a triaxial ellipsoid regardless of its orbital parameters.”  Or in simpler terms: “round objects in space that are smaller than stars”.   The definition excludes stellar objects such as neutron stars, white dwarfs, and black holes.  The proposals are being looked into, but there is no official news if Pluto will change its status once again.

                “I love Pluto”, said Mr. White, “but what about planet 9?” Planet 9 or as it has also been called, “Planet X”, is a planet in our solar system that is “predicted but undiscovered”, according to NASA.  It is supposed to be significantly larger than Earth.  Mr. White predicts a “serious search” for Planet 9. 

                Whether Pluto should or shouldn’t be considered a planet is prominent question in the astronomical science community but another question has been asked about Pluto for more than 10 years.  The real question is, how is Pluto a dog and can’t talk, but Goofy is a dog and can talk?