Natalie Robinson, age 12, of Bountiful, Utah, for her question:

Where does dust come from?

If you are one of the lucky young persons, they give you a chance to try your hand at some of the household chores. For example, it is quite interesting to do the dusting duties on a regular basis. It's easy enough to figure out how the sand got on the bathroom floor or how tome a wad of kitten fur collected in the corner. But pretty soon you begin to wonder how a new layer of dust can appear on the furniture    day after day.

Our everyday world is a lot busier than it seems to be. Floors and walls, ceilings and furniture are made of small particles. These objects get a lot of wear and tear and their surface particles are forever flaking off and falling away. This also happens continuously to rocks and buildings, to the trees and the ground and everything outdoors. These particles float around in the air, wafted by drafts and breezes    indoors and outdoors. When they drift into a room, where the air is calm, sooner or later these fine fragments of wear and tear settle down and cover the furniture with dust.