An astronomy teacher prepared two boxes filled with joke cards. The first box was designed with asteroids and the second one with comets. He then let one of this students pick a box... The student picked the one designed with asteroids. He pick one card and read the joke out loud to the class. The class, however, doesn't find the joke funny. Seeing this, the professor made the student pick another card on the same box. Same thing happened. The confused student look at his teacher and said, ""Sir, I think there is no funny joke in this asteroid box."" The teacher then replied, ""Hmmmm..That's strange. I guess the real joke is in the comets.""