April 11, 1979, at 13:13CST, the Apollo 13 launched from the Kennedy Space Center in Brevard County, Florida. 2 Days into the mission, while on the way to the moon, a short in the electrical system caused an oxygen tank to explode, causing both oxygen tanks to fail and also causing an extreme loss in electrical power. The crew on land and in space worked together to figure out a way to bring the astronauts home safely. The original goal of the mission was a moon landing, but that had to be scrapped in favor of not killing the astronauts. They used gravity from the moon to sling the ship back around towards earth, conserved power and managed to bring everyone back safely. The famous phrase "Houston, we have a problem" is actually a misquote from the mission, when Commander James A. Lovell said "Houston, We've Had a Problem".
Superstitious people have associated the belief that 13 is an unlucky number with the mission. The mission began on April 11, 1970 (4/11/70, the individual numbers adding to 13) at 13:13 CST from Complex 39 (three times thirteen). The mission's problems began on April 13, and the mission itself was called Apollo 13. Other coincidental appearances of the number 13 connected to the mission included the explosion occurring at 19:13 CST, and a post-flight estimate that, had the explosion occurred on the ground, repairing the damage would have cost $13 million. In a feature on the making of the Apollo 13 film, Jim Lovell pointed out that NASA has never had another spacecraft numbered 13. However, in NASA's preliminary schedule for the return to the moon, an upcoming spaceflight is to be called Orion 13.