Pluto’s Back?


Anyone who was in school before 2006 grew up saying Pluto was a planet. No one ever expected that something like this would change, however it did when the International Astronomical Union came up with three things to determine whether something would be considered a planet.

  1. Orbits the sun
  2. Is round or nearly round
  3. Has cleared the neighborhood around its orbit

Although Pluto qualifies for the first two requirements, it was kicked out of its role as a planet because astronomers said it was too small to knock other rocks out of it’s orbit. Because of this, our dear Pluto was demoted to a dwarf planet. But don’t worry, it may be making a comeback!

According to Amanda Barnett of CNN, “[the IAU’s] definitions — and the public’s attachment to tiny Pluto — sparked lots of debate. On September 18,the Harvard-Smithsonian Center for Astrophysics jumped into the debate: What is a planet? It had some experts discuss the definition of a planet and then let the audience vote. Guess what? They voted that Pluto is a planet.”

Alan Stern, principal investigator for the New Horizons spacecraft, which was the first spacecraft sent to Pluto, never accepted Pluto being taken out of the list of planets. Stern went on to say, “In fact, if you put Earth where Pluto is, it would be excluded! Any definition of planethood that excludes Earth, in any circumstance, is deeply flawed. After all, if there is any object everyone agrees is a planet, it’s Earth.”

The other eight planets have their own differences to consider. Not a single one is that same. Jupiter and Saturn are gas giants, Uranus and Neptune are ice giants, and Mercury, Venus, Mars, and Earth are all rocky. So why should Pluto not be brought back into the planet family? Many deny that Pluto ever even lost it’s position.

When New Horizons reaches Pluto, many things will become clear. All it has to do is overcome what Stern calls the “seven weeks of suspense,” which will require it to dodge asteroids as it makes the journey to distant Pluto. The debate over Pluto’s planetary status may not be brought to an end, however we will finally have “detailed, amazing photos of the tiny world, [and] planet or not, Pluto is finally coming into focus.” according to Amanda Barnett.

Viva la Pluto!