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Jim Lovell's line "I vonder vere Guenter vent" was made popular by the crew of Apollo 7. Guenter Wendt was NASA's "pad leader" during the Apollo program and was the last man seen by crews before liftoff. After Wendt closed Apollo 7's hatch and his face disappeared from the window, CSM pilot Donn Eisele said, "I wonder where Guenter went." Commander Wally Schirra claims to have stolen the line and made it famous among astronaut crews.
In a commentary track, Marilyn Lovell comments that Tom Hanks exactly portrays Jim Lovell's mannerisms and style of movement.
Bill Paxton, Tom Hanks and Kevin Bacon were all very proud of the fact that they weren't sick on the so-called Vomit Comet - the plane used to simulate zero gravity. The cameramen weren't so lucky.
In some scenes where the Earth can be seen from the windows of Apollo 13, it is one of the photos taken by Jim Lovell and Bill Anders on the Apollo 8 mission.
Jim Lovell wore his old Navy Captain's uniform in the scene where he greets the astronauts aboard the U.S.S. Iwo Jima. When Ron Howard asked Lovell if he'd like to be in the film as the ship's Admiral, Lovell agreed, but pointed out, "I retired as a Captain; a Captain I will be."