Antionette Smith, age 12, of Winston Salem, North Carolina, for her question:

Why do the stars disappear in the daytime?

An hour before dawn, the stars are out in full array. Then, as the rising sun pokes its bright fingers above the eastern horizon, they begin to dim and one by one their twinkling lights disappear from the sky. They remain in hiding all through the day. In the evening, the sun begins to sink below the western horizon. Then one by one the stars reappear in the twilight sky. Does their appearance and reappearance have something to do with the sun? Indeed it does.

During the day, the sun sheds its light on the earth and strews its dazzling brilliance all through the atmosphere overhead. The stars cannot compete with all this razzle dazzle. In a dark room a small candle seems to glow with a bright flame. But when we switch on a vivid electric light, it seems to fade and grow pale. This is what happens to the stars when the daytime sun appears. Their small twinkles are masked and hidden by the brilliant, sunlit atmosphere above our heads.