In this activity, you’ll learn what it’s like to walk on the Moon. You’ll learn some basic gait analysis by analyzing your own walking and running here on Earth and by identifying the gait patterns used by astronauts when they navigate the reduced gravity environment on the Moon. You’ll also learn about spacesuit pressurization and mobility with a hands-on demonstration.
Background - 5 minutes
Introductory Video: Moon Bloopers!
Activity: Walking on the Moon - 30 minutes
What’s different about walking on the Moon? (discussion / brainstorming)
Gait Patterns on the Moon
Spacesuit Mobility: “Bending Under Pressure”
Wrap-up - 10 minutes
5. How can we improve astronauts’ ability to move around on the Moon?
6. “Bending Under Pressure” Part 2
The student will:
Learn about gait patterns and how they change in lunar gravity
Learn how pressurization in a spacesuit reduces human mobility
What’s so different about walking on the Moon? It’s helpful to think about gravity when we think about locomotion. Every time we walk, step, or jump, we have to act against the force of gravity, that is constantly pulling us toward Earth. The force of gravity due to the Moon is only 17% of the force of Gravity on Earth. That means if you took a scale to the moon and weighed yourself, you’d only be 17% of what you weigh on Earth. Calculate your lunar weight below!
___________ lbs x 0.17 = _______ lbs
Weight on Earth Weight on the Moon
Check out this video of Apollo astronauts walking on the moon:
(Tip: Listen Carefully at 1:08 to hear Apollo 12 Commander Pete Conrad say “I feel like Bugs Bunny”)
A small, open area or hallway where the student can walk, run, and skip
An empty plastic bottle
A phone with camera to capture video (optional)
Now let’s talk about how humans move on Earth. Specifically, you’re going to do some analysis of your own gait patterns (parents or facilitators, you can help by taking the video for your students!).
You’re going to record a video of different gait patterns so you can analyze them (tip: use the ‘slo-mo’ setting on your camera if you have one). If you can’t record a video, ask a friend or family member to help you fill out the gait pattern analysis (and you can do the same for them!).
Record three videos: one of yourself walking across the room, one of yourself running across the room, and one of yourself skipping across the room.
What’s so different about each of these gait patterns?
Using the template below, draw the pattern for running and skipping, using walking as an example. Each foot is represented by a different color. The horizontal axis is time, so the size of each block represents how long each foot is on the ground (an answer key is provided at the bottom of this document).
Things to consider:
Which gait patterns always have at least one foot on the ground?
Which gait patterns have a “flight phase”? A “flight phase” is a period of time during gait when both feet are off of the ground at the same time.
What makes skipping different than walking or running? (Hint: in which order do the left and right feet touch the ground?)
Researchers on Earth look at human gait patterns to help people with abnormal gait. This is called gait analysis. Researchers and physical therapists use this information for rehabilitation to improve a person’s ability to walk.
Now take a look at the “Moon Bloopers” video again. Can you find parts of the video when the astronauts are walking or running? (Hint: There is a much longer “flight phase” during running, so it may look very different. There’s one short clip of running at 0:57).
At 1:08, how is the astronaut moving when he says he feels like Bugs Bunny? Draw this gait pattern below.
Most adult humans on Earth don’t use this gait pattern to walk around. What animals can you think of (other than bunnies) that use this gait pattern regularly on Earth? Why might some animals choose this gait pattern, while humans do not?
Now watch this video:
How is the astronaut moving here? Draw this gait pattern below.
Researchers call the above pattern loping. Astronauts sometimes prefer this gait pattern over walking or running on the Moon. Try to “lope” across the room. This should be quite difficult on Earth!
Why might astronauts choose to “lope” or hop rather than walking or running on the Moon?
Why do you think the astronauts have difficulty walking on the Moon?
Astronauts must wear a spacesuit to provide them with breathable air and protect them from the extreme environment of space. Space is a vacuum that experiences extreme cold and heat as well as radiation, and can even have dangerous debris.
Spacesuits are made of many layers--NASA’s current spacesuit has 14 layers! Each layer has a different function, such as providing thermal insulation or protecting against micro-meteorites. One layer consists of a balloon-like bladder to contain the air pressure around the body.
(Activity modified from NASA’s “Bending Under Pressure” activity in Build it with Spacewalks)
Now, you’re going to demonstrate the effect of a pressurized system using a plastic bottle!
Holding a plastic bottle (a water bottle will work!), remove the bottle cap and try to fold the bottle in half.
Now, unfold the bottle and put cap the back on (creating a closed system— like a spacesuit!). Try to fold the bottle in half again.
What do you notice? Is it more difficult to bend the bottle with the cap on or off? (Hint: What happens to the volume of the bottle after you bend it without the cap on?). How does this relate to spacesuits? How do you think you could make it easier to bend a pressurized object like the bottle with the cap on? (Hint: Think about objects that might bend without changing the volume inside. e.g. an aluminum dryer duct or a vacuum hose)
How can we improve astronauts’ ability to move around on the moon? A suit that can bend without changing volume can increase astronaut mobility. But imagine wearing a spacesuit with dryer ducts for arms. It would still be quite bulky and difficult to move in! Discuss ways that you could make it easier for astronauts to move on the Moon (i.e. how can you increase their mobility, decrease bulkiness, and allow astronauts to perform tasks more easily?). What about spacesuit gloves? What do you think spacesuits will look like in the future?
If spacesuits are someday designed to allow for full mobility, what will it be like to walk/run/lope/etc on the Moon? Would it be easier or harder to locomote on the Moon? Could you run farther than you do on Earth? Why?
6. “Bending Under Pressure” Part 2
If you have the materials available, complete the full “Bending Under Pressure” activity in NASA’s Build it with Spacewalks). In addition to plastic bottles, you’ll need:
Flexible aluminum clothes dryer duct (available at hardware store)
Answer Key: Gait Patterns Activity
Why might some animals choose this gait pattern, while humans do not? The most general answer to these questions is that animals will choose to move in the most efficient way possible, with the least amount of energy required. Humans normally choose to walk because (at low speeds) walking does not require as much energy as running, skipping, or hopping. At higher speeds, humans will transition to a running gait, because it is a more efficient way of moving when higher speeds are required.
Why might astronauts choose to “lope” or hop rather than walking or running on the moon?Astronauts can “lope” in the moon’s low gravity levels, even though this gait pattern is very difficult to use on Earth. They sometimes choose to hop, even though this is not a very efficient locomotion method on Earth. There are two main hypotheses:
1) Reduced gravity may change the amount of energy it takes to perform each of these gait patterns, possibly making loping or hopping more efficient.
2) The mobility restrictions of the space suit may make loping or hopping more efficient or more stable.
Note: Reduced gravity alone likely wouldn’t cause the “Moon bloopers” from the first video where the astronauts were having difficulty moving/walking without falling.
Answer Key: “Bending under Pressure”
See the full “Bending Under Pressure” activity in NASA’s Build it with Spacewalks for an explanation of key concepts.
(Sources: Rader AA, Newman DJ, Carr CE. Loping: A Strategy for Reduced Gravity Human Locomotion? In: 37th International Conference on Environmental Systems, 2007.)
As part of MIT’s larger return to the moon, we’re running an online K-12 challenge, and encourage you to submit an entry! The challenge is to design a lunar habitat and submit your designs to our team by May 15, 2020. The winners of the challenge will be selected for a special prize! Details of the competition and how to enter can be found here.