Elaine Enms, age 8, of Winnipeg, Manitoba, Canada, for her question:

 Could a star fall from the Big Dipper?

This is one thing    that we never have to worry about. It is downright impossible for one of the stars to fall out of the Big Dipper.

As a matter of fact, it also is downright impossible for any other star to fall out of the sky. You may not know it, but those things we call falling stars are not really stars at all.

A real star is big enough to swallow our whole world a million times and still have plenty of room for dessert. What we call a falling star is merely a tiny bit of rock or dirt called a meteor. There are millions of those bitsy meteors out there in space, most of them no bigger than grains of sand. Sometimes they crash into the big planet earth. As they come zooming down through the air, they heat up and catch on fire. And for a moment or so these little meteors look as bright as the huge faraway stars.