Left: Japan Aerospace Exploration Agency astronaut Aki Hoshide performs maintenance on the toilet in the Tranquility node of the International Space Station. Right: A space shuttle toilet simulator. NASA/Dave Mosher Before NASA can fly astronauts to the moon, it must design a toilet for the crew. The agency's "Lunar Loo" contest offered $20,000 for a space toilet design that would work both in microgravity and on the lunar surface. The space agency announced the contest winner this week, as well as the designs that took second and third place.