Mark Brindley, age 8, of Logan, Utah, for his question:

What if the earth had no moon?

The earth is the only planet in the Solar System with just one moon. The other planets have more than one or none at all. And compared with the earth's size, no other planet has a bigger moon. Our planet and its sole satellite are more evenly matched than any others in the Solar System. The pair of them are governed by cosmic laws and forces and they have tremendous influences upon each other. Some of these influences are direct and easy to observe, others are more indirect and not so well understood.

If we lost our golden moon, two very noticeable changes would occur at once. There would be no waxing and waning moon in our skies to add its light to the starry nights. The dependable daily ocean tides would cease and the restless oceans would be moved only by the changeable winds. Many beaches would be stale and stagnant and no tidal water would wash the daily debris from the sands. Lunar gravitation also influ¬ences the earth's motions of rotation and revolution. Subtle changes might occur in its yearly orbit and its day and night period. We might have to adjust to a slightly new time schedule and certain animals would have to adjust to a world of moonless nights.