A picture of a rocket. (Courtesy to Microsoft Encarta for this photograph.)

The rocket is a self-propelled device that carries its own fuel. It also carries the oxygen, or other chemical agent, needed to burn the fuel. Most rockets move by burning their fuel and expelling the hot exhaust gases The force of these hot gases shooting out in one direction causes the rocket to move in the other direction.

Rockets might look very big. At the very top is a small capsule. That is where the astronauts stay. The rest are just fuel tanks. They carry a lot of fuel. When the rocket gets higher and higher, more fuel gets burned. When all the fuel is burned in each of the air tanks, the drop off. Eventually, all that is left is the small module at the very top. When coming back down there is a parachute that comes out of the capsule. The capsule then lands in an ocean and the astronauts make it home safely.