Mike Niederpruem, age 10, of Indianapolis, Ind., for his question:

HOW DO THE STARS FORM CONSTELLATIONS?

Picture the earth as a spinning globe, surrounded by the vast reaches of star studded space. From its surface we see a part of the enormous galaxy, strewn with a few thousand neighborhood stars  all swinging around together. Some look bigger and some look dimmer, though we cannot tell which ones are nearer to us or farther away.

However, we can see groups of neighboring stars in this direction and others in another direction. These are the familiar patterns that form the starry constellations. Actually the positions of the stars in relation to the earth are changing. But the oceans of space are so vast that we see no change during a lifetime. Most of the constellations looked the same more than 2,000 years ago  though many changes appear after a million years.