Hubert Schmidt, age 14, of Miami, Fla., for his question:

WHAT IS THE DIFFERENCE BETWEEN A REFLECTING AND REFRACTING TELESCOPE?

A telescope is an instrument that magnifies, or makes larger, objects that are seen at a great distance, such as the moon or stars.

The simplest type of telescope used by astronomers is called the refracting telescope. At one end of the tube is a small ocular, or eyepiece, consisting of two lenses. It is through this part of the telescope that the image is seen and by which the image is magnified. At the other end of the telescope is a convex lens called the objective or object lens, and it is the lens that gathers the light.

A reflecting telescope is made of a heavy tube. One end of the tube is open and at the other is a large mirror. The eyepiece is located at the side of the tube at a 90 degree angle. As the light waves enter the tube, they are reflected by the mirror to another mirror and then to the eyepiece.