Science Secrets · Drawing 18 of 40
A Balloon Rocket Takes Off
Space
When air leaves the balloon in one direction, the balloon is pushed the other way. Rockets also move by expelling matter. Here is a little action-and-reaction experiment!
Did you know?
A rocket can move through the vacuum of space.
Look together
Which way would the balloon move?
An idea to try
An adult prepares a balloon taped to a straw on taut string. Predict its direction before letting it deflate.
For the adult reading along
A little more to discover
The expelled air and balloon exert opposite forces. A rocket does not need to push against outside air. The setup guides the balloon along the string.
Sources and illustration notes (1)
Simplified scene and shapes. Models, imagined comparisons and enlargements do not preserve all real measurements.
These links lead to other websites. Explore them with an adult. References identify the institution and the related lesson; some linked pages are in French.
- NASA Glenn: Rocket ThrustWhen air leaves the balloon in one direction, the balloon is pushed the other way. Rockets also move by expelling matter. Here is a little action-and-reaction experiment!
Source review: 2026-10-12. Illustrations are simplified for colouring.
