Gravity

The gravity of the world is very powerful. That is why it is difficult to get into Space. The space shuttle beats gravity by having very powerful rocket engines. They make it grow very much faster than a rifle bullet. In Space, it travels hundreds of kilometres every minute.

What happens when i throw a ball into the air? It goes up a little way and then falls back to the ground. When apples are ripe, they fall of a tree. If i jump up in the air, i soon come down again. Something is pulling you, the ball and the apple back to the ground. It is a force i call gravity. Gravity keeps people in the ground, the waters in the oceans, and the air in the atmosphere. It also goes out a long way in Space. It even keeps the Moon in place thousands and thousands of kilometres away!

Up in Space, astronauts do not seem to be affected by gravity. They feel weightless and just float about like this astronaut in the space shuttle's cargo bay.

It is gravity that gives me my weight. Weight is force with which the Earth pulls my body. It is not the same as my mass. Mass is the amount of a stuff in my body. This never changes. But my weight can change, if gravity changes.

If i went far out into Space, i would find that i seem to be weightless! I would just float about as if there was no gravity. Gravity is still there, but its pull on my is tiny because of the way my are travelling in Space.