Video: Gravity Realized

What would it be like if you could see the planets of our solar system orbiting the Sun all at once? What about the moons orbiting the planets? Learn how to make your own simple demonstration of gravity and planetary orbits in this fun activity. Read more

Why can we feel gravity pull us down towards the Earth, but not sideways towards other big objects like buildings? Why do the planets in our solar system orbit the sun instead of flying off into space? In this lesson plan your students will develop a model for gravity and use it to explore answers to these questions. Read more

Why do the planets orbit the sun without flying off into space? Do they move in perfect circles or do their orbits take a different shape? And how could you possibly do a science project about any of this—you can't do an experiment with the planets! However, you can build a model of our solar system that demonstrates the concept of gravity, using balls of different sizes to represent the sun and planets. Watch the summary video for an excellent introduction to the model. Think about how… Read more