Tonya Johnson, age 11, of Tulsa, Oklahoma, for her question:

How did the stars form the Big and Little Dipper ?

These and other constellations form by chance, just because we happen to be viewing them from our particular home in the heavens. If we traveled a few hundred light years out into space, the Big and Little Dippers would be very different. We eight see those same stars, but they would be arranged in different patterns. Actually, they just happen to be out there in more or less the same direction from the earth.

Some of these stars are much closer to us than others. But we cannot observe this by gazing across the vast oceans of space. To our eyes they seem to be related to each other. Actually they are widely separated and most of them are moving in different directions. These changes are not noticeable through several lifetimes. But in 100,000 A.D., the Big Dipper's handle will be almost straight.