Max Kennedy, age 17, of Poughkeepsie, N.Y., for his question:

CAN YOU EXPLAIN ZODIACAL LIGHT?

Zodiacal light is a cone shaped glow of faint light which is seen

in the Northern Hemisphere. It appears soon after twilight on spring evenings and just before dawn in the autumn. It extends upward and southward from the position of the sun.

The zodiacal light is so named because it is seen against the zodiacal constellations which lie along the ecliptic, or the sun’s apparent path around the earth.

The accepted explanation of the light is that large numbers of small particles of material scattered about the inside of the earth’s orbit reflect sunlight and become visible when the earth is dark.

In the tropics the zodiacal light can be seen both evening and morning throughout the year. The light is brightest near the sun and shades off gradually. It can easily be traced halfway across the sky.

Some observers have said they can trace the zodiacal light completely around the sky. They say they notice a brighter area just opposite the sun, called the Gegenschein, which means counterglow.