The Facts about Pluto
You've heard the news: NASA’s New Horizons spacecraft has released the first images of dwarf planet Pluto. Dwarf planet? What does that mean? It’s smaller than any other planet. It’s even smaller than many of the moons orbiting other planets, including Earth.
Pluto has more similarities to the terrestrial planets (Mercury, Venus, Earth, and Mars) than its neighbors, the gaseous Jovian planets (Jupiter, Saturn, Uranus, and Neptune). For this reason, scientists believe that Pluto did not originate in the solar system, but was somehow caught in the sun's gravity.
Here are the basic facts:
- Pluto is so far from Earth that scientists have known little about it until the New Horizons mission.
- Pluto's orbit is unlike the orbits of other planets in our solar system, all of which orbit the sun in a near-circle. Pluto’s orbit is oval and tilted.
- Pluto has five moons: Charon, Styx, Nix, Kerberos, and Hydra. Charon, the largest of the five moons, is about half Pluto's size.
- In 2006, Pluto's official status in the solar system changed from "planet" to "dwarf planet."
To learn more about Pluto see Characteristics of our Solar System.
Pluto as a Symbol for Students and Teachers
Pluto is mysterious, unexplored; we want to know more about it. As teachers, we also want to learn about our students’ talents, their unique personalities, how to motivate them, how to pique their interests. We're enthusiastic about transforming students’ thinking by offering new concepts and skills. Not only does Pluto represent the unknown, but like Pluto, our students come to us with mysterious qualities we are challenged to unlock and understand.
When Pluto's status changed from "planet" to "dwarf planet" many people protested. They claimed the vote was unfair since a small percentage of the world’s astronomers participated. This action was viewed as a demotion, a rejection based on size. Pluto’s planetary status is thus not just a scientific issue but a cultural one. After all, didn’t we learn “My very educated mother just served us nine pickles: Mercury – Venus – Earth – Mars – Jupiter – Saturn – Uranus – Neptune – (Pluto).” Now that old sentence doesn’t make any sense!
Science aside, for some teachers, leaving out Pluto has a symbolic feel, like leaving out one of our students. We work so hard for the underdog students that part of us can’t help but root for the underdog Pluto.
Pluto's status as a dwarf planet inspires love. Signs of that love are evident in all the “Save Pluto” merchandise, such as t-shirts, bumper stickers, mugs, and other items. Symbolically, Pluto’s distance inspires us to advance space exploration technology. If we put forth the effort, we can bring back truth from the frontiers. Discoveries by Hubble and New Horizons give humanity hope for the future.
Hope for the future, isn’t that why we are educators?
You can encourage students’ curiosity about Space Exploration and STEM Careers by sharing a copy of Reach for the Stars.