The Untold Truth Of Apollo 13

Space travel doesn't allow a lot of wiggle room for mistakes because the stakes are so high. For instance, as Space.com recounts, if the Apollo 11 moon landing hadn't ended with a small step for man but instead a misstep that stranded men on the moon, President Richard Nixon planned to deliver a eulogy to the nation before NASA cut communications with the astronauts. Buzz Aldrin and Neil Armstrong would have been left to contemplate the infinite nothingness that awaited them.

Fortunately, no one heard Neil Armstrong say, "Houston, we've had a problem here" in 1969. But those famous words were spoken by Jack Swigert aboard Apollo 13 the following year. The problem Swigert was referring to was an oxygen tank that exploded, per History. Recalling the crew's plight, astronaut James Levell writes, "I did, of course, occasionally think of the possibility that the spacecraft explosion might maroon us in an enormous orbit about the Earth — a sort of perpetual monument to the space program. But Jack Swigert, Fred Haise, and I never talked about that fate during our perilous flight."

Dying in orbital limbo would have been a depressing contradiction, an end that was also endless. But the astronauts aboard Apollo 13 had more important matters to consider, like surviving. "Survive we did," writes Lovell, "but it was close."

Mistakes that tanked the mission

Sometimes hindsight is just foresight you overlooked the first time. In the case of Apollo 13, the same oversight was committed twice. As History details, the fuel cells for the flight relied on two tanks of liquid hydrogen and two oxygen tanks. Oxygen tank No. 2 had sustained unseen damage before its use on the 1969 Apollo 10 mission. Prior to Apollo 13's launch, oxygen tank No. 2 malfunctioned during testing. James Lovell elaborates: "The tanks normally are emptied to about half full, and No. 1 behaved all right. But No. 2 dropped to only 92 percent of capacity."

Two weeks before the mission, tank No. 2 refused to empty correctly a second time. "With the wisdom of hindsight," writes Lovell, "I should have said, 'Hold it. Wait a second. I'm riding on this spacecraft. Just go out and replace that tank.'" Evidently, everyone involved preferred to see the glass as half full when it really needed to be half empty. But an attempt to empty the tank using heat inadvertently turned it into a time bomb.

Houston has a solution

On April 13, 1970, a bomb masquerading as an oxygen tank detonated on Apollo 13. The crew had to move from the damaged command module to the landing module, Aquarius. As History notes, Aquarius wasn't meant to be powered up until the planned moon landing was imminent. Now it would have to sustain three men for 90 hours as they made their hectic descent into Earth's atmosphere. The astronauts had to conserve energy and deny themselves water in order to cool the module's hardware.

Even breathing posed a problem as the crew's restrictive surroundings filled with carbon dioxide. Luckily, Mission Control came up with a clever fix. The astronauts would build a "mail box" to help purge the gas using cardboard, plastic bags, duct tape, and, according to James Lovell, even a sock. Though things had gotten off on the wrong foot, and the men didn't set foot on the moon, the dramatic rescue that ensued yielded valuable insights. NASA classified the mission as a "successful failure."