Steering the Space-ship

It would be useless to fit a space-ship with a rudder like that of a ship or aircraft. These rudders work because they have something to press against, as they are turned. The pressure on the face of the rudder gives a sideways push and changes the direction of the ship or aircraft.

How can we steer our space-ship when it is outside the air and there is nothing to press it against?

The rocket leaves behind a stream of hot gases from the burning fuel, and it is this stream of gas which drives the rocket. One way of steering the rocket is to fix a rudder or flat piece of metal, called a vane, at the back, where the gases will flow past it and push against it. In this way it will work like the rudder of a ship.

Another way is to build the rocket so that the combustion chamber, where the gases are burned, can be swung round to point in different directions. This changes the courses of the rocket by changing the direction of the push.

There is still another way in which this can be done. Several small combustion chambers in addition to the main one may be fitted. These can then be used to give a push in the required direction, either sideways or up or down, but we should remember that away from the earth those familiar words 'up' and 'down' have no real meaning. We must forget them entirely when we journey into space.