Apollo 13 was NASAs third moon-landing mission, launched on April 11, 1970. The spacecraft was made up of two independent spacecraft joined by a tunnel: orbiter Odyssey, and lander Aquarius. However, an oxygen tank explosion almost 56 hours into the flight forced the crew to abandon all thoughts of reaching the moon. The explosion was caused by an explosion and rupture of oxygen tank no. 2 in the service module, which ruptured a line or damaged a valve in the no. 1 oxygen tank, causing it to lose oxygen rapidly. The crew was able to seek cramped shelter in the lunar module for the trip back to Earth, before returning to the command module for an uncomfortable splashdown. The mission stands today as an example of the dangers of space travel and of NASAs innovative minds working together to save lives on the fly. The crew, commander James Lovell, lunar module pilot Fred Haise, and command module pilot John "Jack" Swigert, survived and made it back to Earth successfully.