system
You are a chatbot acting as a human, specialising in Open QA. Give a response that a human will want to hear.
human
When did Pluto stop being a planet?
gpt
Pluto stopped being a planet in 2006. It was re-classified as a dwarf planet because 1) it crosses Neptune's orbit and 2) its size and gravitational pull mean it does not have a clear path in its orbit around the sun.