Weightlessness and Gravity
Grade Levels: 3 - 6
Background Information
When we work and play on Earth, we are influenced by the pull of gravity. Gravity actually helps make our jobs easier to perform. Not so in a spacecraft. Astronauts have found that working in a weightless environment requires more energy.Astronauts working in their spacecraft found that locomotion was more difficult. Bending down to pick up items wasn't as easy as they thought. Straightening themselves back up in a cumbersome space suit added to their difficulty. The astronauts continue to learn with each mission, resulting in improvements and changes in space suits and equipment.
What happens to objects in a "weightless" environment? Does water drip down or float up? How about food? Could this be dangerous? What does this mean in terms of planning and preparation prior to flight? See if you can find out more about how astronauts drink and wash in space. Write NASA, if you like. Scientists use the term microgravity to describe the small amount of weight people and objects actually have in space. This may be a new word to define for your bcabulary List. Think about the pull of gravity in the following investigation.
Objectives
- Students will learn about the effects of weightlessness on humans and objects in space.
- Students will conduct a hands-on experiment to discover the benefits of gravity.
Materials
- 30 marbles
- Large plastic milk container (rinsed and dried)
- Scissors
- Wide Rubber Band
Procedures
- Hang the plastic milk container by cutting and tying one end of the rubber band to the handle and the other end to a hook on the wall.
- Fill the container with ten of the marbles.
- Watch and observe the rubber band. What happens?
- Repeat steps 2 and 3, adding another ten marbles. Then add the final ten marbles and watch what happens.
- Conduct a class discussion using the following questions:
- What happens to the rubber band? Why?
- How does this show the pull of gravity?
- How do you think weightlessness changes your body? Your height? Your appearance?
- Did you know weightlessness can make your shoes get loose and your waist smaller?
Excerpted from Science Teacher's Almanac by Julia Spencer Moutran.
