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Expanding Universe: Balloon Model

Expanding Universe: Balloon Model

Ages 6-1210 minutesEasy Difficulty

About This Activity

This experiment helps you visualize how galaxies move apart as the universe expands, just like the Big Bang theory predicts.

Materials Needed

  • A balloon
  • A marker

Safety Notes

  • Be careful not to pop the balloon while inflating.
  • Supervise younger kids when handling balloons.

Instructions

  1. 1. Before inflating, draw several dots on the balloon with a marker. These dots represent galaxies.
  2. 2. Slowly blow up the balloon and observe what happens to the dots.
  3. 3. Notice how the dots move farther apart as the balloon expands, just like galaxies in our universe.

How It Works

As the balloon expands, the dots move farther apart without actually moving themselves. This models how space itself stretches, causing galaxies to move away from each other.

Tips for Success

  • Try marking one dot as 'Earth' and see how all the other dots move away from it.
  • Use different colored markers to see how galaxies shift over time.