Regina Hudson., Age 13, Of South Charleston, W. Va... For her question:

What is meteoric dust?

If you watch the sky on a clear night, you are sure to see a few falling stars. Most of these blazing meteors are small specks of matter no bigger than grains of sand. We see only a few of them, but records show that millions of them strike the earth every day. These small meteors burn to ashes long before they reach the ground.

The dusty ashes from burned meteors may stay aloft., drifting through the atmosphere for a long time. But sooner or later the microscopic fragments fall down to earth. It has been estimated that four ounces of meteovic dust falls upon each square mile of earth during a year. In 5 billion years,, this would add a layer of about one inch of meteoric dust around our entire globe.