Rosemary Lizardi, Age 12, Of Tucson, Ariz., for her question:

Do the fixed stars move?

The fixed stars are those of the familiar constellations in our skies. They certainly seem to move, to rise and set and change with the seasons. But these are merely apparent motions caused by our rotating and revolving globe. However, as we observe them, their eternal patterns form a fixed background for the wandering paths of the planets.

We cannot observe the true motions of the stars, because the changes take too long. Nevertheless, the fixed stars move. They revolve at different speecis around the Milky way. Our starry sun and its planets also revo1ve around with this giant Pinwheel of stars.