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Home » Science Experiments for Kids » Space Experiments » How does the Universe expand?

How does the Universe expand?

Modified: Oct 26, 2023 · Published: Jun 1, 2012 by Emma Vanstone · This post may contain affiliate links · 7 Comments

Today we have an investigation for little astronomers to demonstrate how the universe is expanding.

Did you know we are part of a spiral galaxy called the Milky Way? Earth is located in an arm of the spiral.

Diagram of the expanding universe

What is the Universe?

When we talk about the universe, we mean everything that exists. Galaxies, planets and everything in between. Scientists think the edge of the universe is expanding faster than the speed of light!

How big is the Universe?

It’s hard to imagine just how big the universe is. Scientists estimate that there are around 100 billion galaxies!! If you think the Milky Way ( our galaxy ) is thought to have between 200 and 300 billion stars like our sun, it’s pretty impossible to comprehend.

Much of the universe is actually empty space ( dark matter and dark energy ) and the things we can see ( ordinary matter ) make up only 4-5% of the universe.

What is dark matter?

Scientists think stars and planets would not move as they do in empty space, but so far we don’t have the ability to see or measure dark matter. Dark matter is thought to make up between 25-28% of the universe.

What is dark energy?

Dark energy is how scientists refer to the force that is thought to be behind the expansion of the universe. Dark energy is though to make up between 67-70% of the universe.

Universe Expansion Theory Demonstration

This is a very simple experiment to demonstrate the Universe expansion theory.

You’ll need:

A balloon

Clip

Black Marker

How to demonstrate the expansion of the universe

  • Blow up the balloon so its about the size of an orange.
  • Clip it with a balloon clip.
  • Draw dots on the balloon with a black marker, these represent the the milky way galaxy.
  • Remove the clip and keep blowing up the balloon.
  • What happens to the dots?
How does the universe expand

How does the universe expand – explanation

The balloon is a model of the universe, which is constantly stretching outwards. The universe has been expanding ever since the big bang about 13.8 billion years ago.

Expanding Universe experiment sheet

More Space Science Experiments for Kids

Discover how craters are formed on planets with this crater investigation.

Even very small children will love our rocket mouse!

Find out when the Earth formed and how we know!

Science concepts

The big bang

Universe

Dark matter

Image of the universe expanding for a science activity.

   

Last Updated on October 26, 2023 by Emma Vanstone

More Space Experiments

  • Diagram of the Solar System showing the planets in orbit around the Sun
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Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

Reader Interactions

Comments

  1. maryanne @ mama smiles

    June 03, 2012 at 10:38 pm

    I love this visual representation!

    Reply
  2. Marnie @ Carrots are Orange

    June 04, 2012 at 6:14 am

    Love this approach! I bet my boy would really “get it”…thank you for sharing…

    Reply
    • ScienceSparks

      June 04, 2012 at 11:50 am

      I’m glad you liked it! xx

      Reply
  3. Laura White

    June 05, 2012 at 4:01 pm

    My three year old granddaughter will love this. Finding things to do for preschoolers in science is not that easy. We have just started to study the solar system this will be great.

    Thank you,

    Laura

    Reply
  4. Ticia

    June 08, 2012 at 8:09 pm

    Ahhhh, but is it a cycle of expanding and collapsing or does it expand forever? I always thought that was an interesting debate when I was in school. I’m weird that way though.

    Love the visual.

    Reply
  5. sally

    December 04, 2019 at 9:50 pm

    loved it for a school progect

    Reply
  6. TD19

    January 24, 2023 at 2:15 pm

    Loved it!!! This is so helpful for my science projects, thank you so much!!!

    Reply

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