In the mystical land of Pyros, Aarav has a magical mirror that shows the opposite of what is true. When he holds an apple in his left hand, the mirror shows it in his right hand. One day, Aarav stands facing the mirror and sees his friend Keiko approaching him from behind in the reflection. Keiko is holding a bright lantern that always burns with a blue flame. However, in the reflection, the flame appears orange. Given the properties of the mirror, what color is Keiko's flame in reality when Aarav turns around to greet her? Provide a very short response.
The magical mirror shows the opposite of what is true, so when Aarav sees the blue flame as orange in the mirror's reflection, the actual color of Keiko's flame must be blue. This is because the mirror inverses what Aarav sees; thus, when he turns around to greet Keiko, he will see a blue flame on her lantern.