Sue Coloton, age 12, of Utica, New York, for her question:

What does a ring around the sun mean?

Some people read weather signs into such things. When the sun is circled with a pale ghostly halo, it is supposed to mean that rain can be expected soon. Very often this weather prediction comes true. This is understandable when we know what causes these solar halos. Naturally, they are not attached to the starry sun, which is 93 million miles out there in space. What we see is in our own atmosphere, just a few miles above the earth.

The air contains tons of gaseous water vapor that continuously forms clouds of misty moisture or tiny ice crystals. Sometimes a filmy veil of icy crystals spreads all over the sky, rather high above the ground. This is when solar halos are likely to be seen. They occur when the sun's rays are bent or refracted by those glassy crystals of ice. At such times there is plenty of moisture in the upper air. A slight change in weather conditions might, or might not change it into rain.