40-three years ago today, the Apollo 13 spacecraft splashed down into the Pacific Ocean following one of the most remarkable recovery missions in space history. Inside was mission commander Jim Lovell, 42, lunar module pilot Fred Haise, 36, and commander module pilot Jack Swigert, 38.
Apollo 13 was supposed to land on the moon, but an explosion in one part of the spacecraft less than three days after launch forced NASA to abort the mission. The mission is still considered a “successful failure” because the three astronauts returned to Earth safely.
Day 0 (Pre-launch): Fred Haise (left), Jack Swigert, and Jim Lovell pose on the day before launch. Swigert replaced Ken Mattingly as command module pilot just 48 hours before launch after Mattingly was inadvertently exposed to German measles.
Day 1 (Launch): Apollo 13 blasts off from Florida's Kennedy Space centre on April 11, 1970 at 1:13 p.m.
The Apollo spacecraft was made of three main parts: The command service, the service module, and the lunar module. The command and service modules (together called CMS) were attached to the lunar module by a tunnel. Here's a complete diagram of the space vehicle.
The Apollo crew lived in the command module. The service module housed the main propulsion system as well as fuel cells to provide electrical power to the crew.
Two tanks of liquid oxygen in the service module allowed the astronauts to breathe. The oxygen was also used to power the fuel cells that generated electricity to run the spacecraft. This is a diagram of oxygen number tank number 2.
A few minutes later, ground control asks Swigert to perform a routine procedure called a cryo-stir. This involves switching on fans to stir contents inside the service module oxygen tanks, which prevents the liquid from settling into layers.
That gas was the oxygen the crew not only needed in order to breathe, but also to power the fuel cells that generated water and power for the spacecraft. The command module was quickly losing power. The mission was aborted.
Exposed wires shorted when the fan was turned on to stir the oxygen tanks. The spark, fuelled by pure oxygen, ignited the Tungsten insulation. This started a fire inside the number 2 oxygen tank, increasing pressure and causing it to explode. Part of the service module's cover was blown off.
Back in the control centre, NASA had called all of its top people in within a few hours of the explosion.
This would present several future challenges. The lunar module was only designed to support two men for two days (like in this artist's concept of Apollo 13 astronauts exploring the moon's surface). Now it was being used to support three men for about 90 hours. The crew had enough back-up oxygen, but the build-up of carbon dioxide would soon be an issue.
The new mission was to get the lunar module in a free-return-to-Earth trajectory. Prior to the explosion, the craft was on course for the moon. The free-return course required slinging the lunar module around the moon, back to Earth, and landing in the Pacific Ocean.
Day 3: A telescope photographs the Apollo 13 spacecraft in the lunar-free return, which will take the craft around the far side of the moon, and back to Earth.
Day 4: After a day and a half in the lunar module, a warning light goes off showing dangerous levels of carbon dioxide. The crew could use the canisters used to remove carbon dioxide from the command module, but there was one problem: The command module used square canisters, while the lunar module used round ones.
Mission control came up with a makeshift system using only materials available on the craft, like plastic bags, cardboard, and tape, to make this work.
It finally sinks in that the crew will not be landing on the moon, but can only watch it as they pass by from a distance.
The crew photographs the far side of the moon from the Apollo 13 spacecraft on their perilous journey home.
The trip is gruesome. There is very little food and water. Most electrical systems, including heat, were shut down to conserve power. The crew can't sleep because it is so cold. At one point the temperature drops to 38 degrees Fahrenheit.
Day 7: Four hours before landing, the damaged service module was released from the command module. The crew snapped pictures, and for the first time, were able to see the full extent of the damage.
An entire panel of the service module had been blown away when the oxygen tank exploded, as seen in this close-up image.
About to splash down in the South Pacific Ocean, the crew moved back into the command module. The lunar module was shed from the command module.
A large screen in front of the mission control room shows the spacecraft with its parachutes deployed.
The spacecraft splashes down on April 17, 1970 at 12:07 p.m. The total voyage time was about 142 hours.
A day later, Lovell reads the newspaper account of Apollo 13's rescue while still on board the U.S.S. Iwo Jima.
President Richard Nixon presents the nation's highest civilian award to the Apollo 13 crew on April 18.
NOW WATCH: Briefing videos
Business Insider Emails & Alerts
Site highlights each day to your inbox.