"Today, everyone is familiar with Neil Armstrong's famous words as he first set foot on the moon: 'one small step for man; one giant leap for mankind.' He made it look easy, but America's journey to the moon was anything but simple. In 1957, when the Soviet Union launched Sputnik, the world's first satellite, into orbit, America had barely crossed the starting line of the great Space Race. Later that year, our first attempt was such a failure that...

"Christopher Columbus is one of the most famous explorers of all time, but he was neither the first nor last adventurer to ever stumble upon a great discovery. From the Silk Road of Asia to the icy shores of Antarctica, our knowledge of the world today is in large part due to several intrepid pioneers, risking life and limb for the sake of exploration. After all, setting off into the dark unknown requires an enormous amount of bravery. But every explorer...