Members of the original Apollo 13 crew, from left, commander Jim Lovell, command module pilot Ken Mattingly, and lunar module pilot Fred Haise pose in December 1969.
Days before the mission, the crew was inadvertently exposed to German measles. Mattingly had no immunity to the virus and was replaced by backup command module pilot, Jack Swigert.
The Apollo 13 Saturn V rocket lifts off from Kennedy Space Center near Cape Canaveral, Florida on April 11, 1970.
An artist's conception from March 1970 shows Lovell and Haise exploring the surface of the moon. Behind them is the lunar module.
But the lunar landing was not to be. Instead, some 56 hours into the Apollo 13 mission, oxygen tank No. 2 exploded, causing oxygen tank No. 1 to also fail. The command module's normal supply of electricity, light, and water was lost as they flew more than 200,000 miles from Earth.
Swigert saw a warning light that accompanied the bang and radioed mission control: "Houston, we've had a problem here."
During Apollo 13's lunar pass on April 14, 1970, the crew captured this view of the Tsiolkovsky crater on the far side of the moon, the hemisphere that always faces away from Earth.
Astronauts and flight controllers monitor the console activity in Mission Control on April 14.
Seated, left to right, are control room guidance officer Raymond Teague and Apollo 14 astronauts Edgar Mitchell and Alan Shepard, both of whom would later walk on the moon. Standing, left to right, are scientist-astronaut Anthony England and backup Apollo 14 crew members Joe Engle, Eugene Cernan, and Ronald Evans.
Cernan became the last man to walk on the moon during the Apollo 17 mission.
Mission Control is a tense scene on April 16 during the final 24 hours of the Apollo 13 mission.
Here, flight controllers and NASA officials confer at the flight director's console, attempting to bring the crippled spacecraft home.
Parisians stop on the sidewalk to read about the Apollo 13 accident.
School children in Coventry, England pray for the astronauts' safe return.
The severely damaged Apollo 13 service module was photographed following its jettison on April 17.
The damage to the service module caused the crew to use the lunar module as a "lifeboat." It was also jettisoned just prior to Earth re-entry later that day.
A Navy helicopter hovers over the Apollo 13 capsule in the South Pacific as frogmen release the astronauts on April 17. The USS Iwo Jima recovery vessel waits nearby.
Flight directors applaud the successful splashdown of the Apollo 13 crew.
Haise steps into the liferaft, center, as the crew is recovered. Swigert, back to camera, is already in the liferaft. Lovell is the last man out of the module.
Lovell is lifted onto a helicopter to be flown to the USS Iwo Jima.
Crewmen aboard the USS Iwo Jima guide the Apollo 13 command module onto the ship.
From left, Haise, Lovell, and Swigert step aboard the USS Iwo Jima.
Marilyn Lovell stands with her children, from left, Susan, Barbara, and Jeffrey, as she speaks to the media after her husband's safe splashdown on April 17.
Confetti pours from skyscrapers in Chicago's financial district on May 1, 1970, as Swigert, waving at left, and Lovell ride in a motorcade during a parade in their honor.