Andy Ayers, Age 9, of Bridgeton, Mo., for his question:

What exactly is atomic energy?

The universe is full of mighty giants. We cannot see them, but we can make them work for us. Electricity gives us light and power. It took ages to tame this gigantic force to be our servant. Now we are taming a greater giant, the force of atomic energy.

Atomic energy is stronger than any other force We have learned to use. To understand it, you must know a few facts about the little atom and then think about the word. Energy. These ideas are not easy, because you cannot see an atom or energy. But your mind can grasp them if you let your imagination come to the rescue.

There are atoms of different sizes, but the same design is used to make them all. All atoms are made of tiny particles of matter, and large atoms have more particles than small atoms. You can imagine an atom if you think of a miniature solar system. Its sun is a tight wad of particles called the nucleus. Its planets are orbiting particles called electrons.

We can imagine an atom, even though it is too small to be seen. It is bound together by energy, which we cannot see either. But when we think of other forms of energy, We can imagine this also. Electric energy can lift a lamp, and energy from steam can pull a train. All energy is force. We cannot See it, but it makes things work. You use energy to run and play, to think and digest your food. An atom uses energy to bind its particles together.

Now comes the hard part. Atomic particles are a form of energy. The atoms which make a solid rock are energy in a kind of frozen form. A fragment of matter can be changed into invisible energy. This is what happens when We free the tremendous force of atomic energy.

Most of the atom's energy is in the nucleus. So long as its tiny particles of matter are held in a tight wad, this enemy is locked inside the atom. But the nucleus can be split, and atom splitting is nuclear fission. It frees energy from the nucleus and changes particles of matter into energy. Atomic energy also is freed when small atoms are forced to make bigger atoms. Not all the particles are needed by the remodeled atoms. In nuclear fusion, these left over fragments of matter are changed into atomic energy.

Nuclear energy, alias atomic energy, is a mighty force with no mind of its own. It must obey the orders of its human masters. Sciene has learned how to free it, and the giant can be used to hurt us   or it can be tamed to become our strongest servant. Naturally we want to tame that giant and make it do useful work for us.