When my teacher, Mr. Albright, told me that our class was going to visit the U.S. Space and Rocket Center in Huntsville, Alabama, I was over the moon. I had dreamed of visiting this museum all year after learning about space exploration in school. Last Friday morning, we met our tour guide, Ms. Randall. She introduced herself and broke the ice by having each of us share our favorite space facts. After visiting several exhibits and the planetarium, I was hungry. Mr. Albright said, “Hang in there, Toby. It’s almost time for lunch.”
What does the idiom, "over the moon," mean?