The Apollo 13 mission was intended to be a "routine" trip to the moon. But when an oxygen tank exploded, the spacecraft was crippled and its 3-man crew placed in mortal danger. The Lunar Module, intended for deployment on the moon's surface, instead became a lifeboat. Scientists and engineers on earth fought a race against time to save the crew. We'll examine the mission, which nearly ended in tragedy, but instead was a resounding success, and in some ways became NASA's finest hour.