Ion Engines are the most exciting new rocket propulsion system since the Chinese invented the rocket about a thousand years ago.

Most rocket engines use chemical reactions for power. They combine various gases and liquids to form chemical explosions which push the rocket through space. Chemical rocket engines tend to be powerful but have a short lifetime.

Ion Engines use electric fields instead of chemical reactions. Ion Engines tend to be much less powerful, but they are so efficient, they can last for years before running out of fuel.

These activities should help you understand how Ion Engines work.

Before you can understand the entire Ion Engine, you need to understand some basics about electric charges.

Play the first three activities to learn about electric charges. Then, try your hand at designing an Ion Engine.

1. Positive and Negative Charges
2. Charge Simulator -- get the charges to hit the targets
3. Hotspots-- play against the computer in this soccer-like action game
4. Design an Ion Engine-- put what you've learned to use