Book 8, Question 43
Why Did Apollo Astronauts Bounce When They Walked?
Apollo astronauts bounced because Moon gravity is about one-sixth of Earth's! The same leg push flings you higher and farther, and the hops look like slow-motion dancing. Less gravity means a bigger bounce!
More fun facts
- The Moon's gravity is one sixth as strong as Earth's, so each push of the legs sends you up much farther and you come down more slowly.
- Apollo spacesuits were filled with pressurized oxygen, which made the suit's legs springy. That springiness helped hold up the weight of the suit.
- The suits were so heavy that running in them under Earth's gravity would take more energy than a person could keep up.
- Neil Armstrong described a lope as having both feet off the ground at the same time, unlike walking, where one foot always stays down.
- During much of the Apollo 11 moonwalk, Armstrong and Buzz Aldrin actually walked flat footed, one foot in front of the other.
- Nobody used the two footed kangaroo hop on level ground except in play, but Gene Cernan and Harrison Schmitt used it to come down a steep hill on Apollo 17.
- Scientists calculated that in Moon gravity, people should switch from walking to running at only about 1.8 miles per hour.
Questions kids ask
Why didn't astronauts just walk normally on the Moon?
Their stiff, pressurized suits and the weak gravity made a bouncy lope easier and more efficient than ordinary walking.