"In 1971, Alan Shepard and his fellow astronauts made their way to the Moon in the cramped Apollo 14 capsule. Their mission: Study the moon in more detail than ever before. While the world watched on TV, Shepard and Edgar Mitchell gathered rock and soil samples wearing stiff, heavy spacesuits. But Alan Shepard had a secret hidden in his sock: two tiny golf balls. Golf was Shepard’s favorite sport. And since the moon has virtually no atmosphere and...