This month, every How It Works reader has a chance to win a NASA Apollo 15 American Moonphase watch by Xeric Watches. The lunar design celebrates NASA’s triumphant mission to the moon in 1971. Along with a pair of lunar hands and a luminous glow-in-the dark coating, this watch tracks the Moon’;s journey through its 29.5-day cycle.
For a chance to win, answer the following question: