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Either Pluto is a planet and Eris and Haumea and Makemake and Sedna and.... are too or you let go of what they taught you in elementary school and be fine with
by hoseja 4y ago
Either Pluto is a planet and Eris and Haumea and Makemake and Sedna and.... are too or you let go of what they taught you in elementary school and be fine with the dwarf planet designation.
- bnralt 4y agoI saw a Twitter post the other day showing the orbit of planets in the solar system that included Ceres. There were tons of replies saying "What's Ceres? Did they discover a new planet?" People would probably have a better idea about our solar system if we taught them that we don't know how many planets are in the solar system, and told them we were going to have some extra focus on the 8 largest (or 13 largest, or 7, wherever you want to draw the line). The IAU definition of planet (which wasn't the original proposal, and which most planetary scientists don't seem to follow) appears to be a conservative attempt to keep the number as close to the "traditional" number as possible, even if it leads people into having an overly simplistic conception of our solar system. And it leaves us with a loose definition that specifically states it only applies to our solar system, and doesn't apply anywhere else in the universe.