Mars is a planet closest to Earth.
When Lisa wins the Springfield Elementary School Spelling Bee, Seymour Skinner awards her with a 'scale model' of Mars, but it is just a kickball with “Mars” written on it. Homer inspects it and says he cannot see any life.
When Lisa foud out about Exploration Incorporated, she vounteers to an one-way journey to Mars that would be launched in ten years. On an attempt to make Lisa give up, the entire family decides to volunteer to the mission, but only Lisa and Marge managed to pass. However, the launch that was scheduled to happen ten years later was moved up to Thursday. During the rocket's launch, they discovered that the rocket was not complete, and it was just a stunt to "inspire the next generation".
- Episode – "One Fish, Two Fish, Blowfish, Blue Fish" (Mentioned)
- Episode – "I'm Spelling as Fast as I Can"
- Episode – "Holidays of Future Passed"
- Episode – "How I Wet Your Mother" (Mentioned)
- Episode – "The Marge-ian Chronicles"