Scott Park, age 9, of Wichita, Kansas, for his question:

What is the meaning of perigee?

The word "perigee" belongs to the space age, and every young space ager should know what it means. It has a partner word called "apogee," and we cannot understand one without the other. Let's begin by thinking of a man made satellite orbiting high, high above the ground on its way around and around the globe. Its orbit goes round and round, but not in a perfect circle. Our satellite has an oval shaped orbit. Its width is a bit shor¬ter than its length. And there is another surprise. The round earth is not exactly in the middle of our satellite's orbit.

This means that part of the orbit is higher above us than other parts. Space experts need to know a lot of math to study the orbit of a satellite. At least we are smart enough to understand two points in the orbit. The perigee point is the one closest to the earth. The apogee point is where the orbit is farthest from the earth. Each time the satellite orbits the globe it passes the closest point of perigee and then the farthest point of apogee.