One day on a walk, my fifth grader and I started talking about the solar system. I thought we'd discussed it before, but in our discussion she said they learned about the planets, and also Pluto the dwarf planet, that some people think is a planet and others think isn't and it's just confusing.
What about the other dwarf planets, I asked. Like Eris, Haumea, Makemake? They hadn't learned about those, she said. They learned that there were lots of other things in the solar system with complicated names, but everyone knows about the planets, and Pluto. She'd never heard of Eris. Well of course Pluto's "controversy" doesn't make much sense if you don't know about the other dwarf planets, I said. Eris is practically the same size as Pluto, heavier, just as important. Maybe even MORE important, because the discovery of Eris and the other planets lead us to question how we should classify everything. Do we add it as a 10th planet? Do we add everything? What else will we find? No, we decided, the trans-Neptunian objects are so much like each other but so different from the first eight planets. They should be their own category.
Dwarf planets are cold and far away and smaller than even our moon. They are also less than half the size of Mercury, the smallest planet. Sometimes they have their own moons. They orbit alongside other asteroids and objects because they're not big enough to have cleared their orbit. We have a lot to learn about them, because they are further than telescopes can see and most spacecraft have traveled. Any time they are discovered, they are worth celebrating. But to me Eris may be the most interesting, because it changed our thinking. At the very least, it deserves a spot anywhere Pluto is mentioned.
The beauty of science is that it changes. Scientists aren't WRONG and then RIGHT. They make the best explanation with the information they have, and when they learn new things, their explanation can change. They can change even if that change blows their minds, takes convincing, goes against their "gut feeling", wasn't the way they were raised, or makes people mad. Scientists look at the data and their understanding evolves. That's why science is so beautiful. With that in mind, I am campaigning for the world to celebrate Eris Day every year on its discovery date, January 5th. I want everyone to appreciate the beauty of changing scientific understanding. Scientists will never be done looking at the universe. It is infinite. We will never know everything. But one thing is for sure: we know more now than we did when I went to school in the 1980s. I learned about the solar system one way, my children can learn about it a different way. Maybe they will discover new things too. I want them to know that there's a place for their discoveries, that we're not dead set on one idea, because science will be open to new explanations based on new evidence.
Celebrations are a great way to bring recognition to an idea, and I think new discoveries are the greatest idea we have. That's why I started Eris Day.