It is all day and night. This is awful, but my 7 year old was never brave enough to ride SM until this year (we had only been to WDW but wouldn't ride it there) We had all heard the term "Ghost Galaxy" and I think she was expecting little Mickey ghosts floating around. None of us thought it would be as scary as it was (and LOUD) Needless to say, she wants to ride SM again, but never during ghost galaxy. My 9 year old that had ridden SM dozens of times refused to go back on it after one try with the ghost galaxy.