Lori Bogisich

My family and I love Jeopardy and have been watching it for many years. My two children have watched it since birth! However, on tonight's show there was a clue "It was identified in 1828 & named for a Norse deity, long before it was found to be a nuclear fuel. I texted a screen shot of the clue to my brother who was taught how to build, maintain and run nuclear reactors. He did so on nuclear navy vessels for many many years. He also taught other navy people how to build, run and maintain them. He guessed "plutonium". I told him it was "Thorium". He said, "Thorium is not a nuclear fuel." How can I ask the Jeopardy people where they came up with Thorium as a correct answer?