A blonde, a brunette, and a redhead, all working for NASA, were trying to figure out where to go on the next trip.
The brunette said, "We should go to Mars."
The redhead said, "We should go to the Moon."
The brunette and the redhead sat there arguing for a while. Suddenly, the blonde shouts, "Stop arguing! I know where the next expedition should be to ... the Sun!"
The brunette and the redhead looked at each other and started laughing. The brunette finally said, "You can't go to the Sun. You would melt or burn up before you even got close!"
The blonde said, "DUH... Not if you go at night!"