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Demonstrate the gravitational centre of the earth and the moon’s orbits

Suitable For

Grade 6



Time Required

 <12 Hours



What’s it about?

Space is full of ‘planets’ or other bodies orbiting one another. All nine of the planets in our galaxy orbit around the sun, and the moons orbit around the planets. Orbiting bodies such as planets and moons have a balancing point called the ‘barycentre’, which is the gravitational centre of their combined orbits. In this science experiment, you will demonstrate this by balancing two clay spheres:

Topics covered


What will I need?


Procedure (Method)

Unfortunately, this section is only available in the e-book version of the project.

How does it work?

Unfortunately, this section is only available in the e-book version of the project.

In this science experiment, the point within the ‘clay earth’ where the string is tied to the pencil, represents the earth’s gravitational centre of the earth and moon’s orbits. This point lies about 4300km beneath the surface of the earth on the side that is facing the moon.

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