Chris Sousley, age 12, of Omaha, Neb., for his question:

WHAT IS THE CELSIUS SCALE?

The Celsius scale is used for measuring temperature. It is a part of the metric system of measurement. Lots of countries use the Celsius scale for everyday temperature measurements although at the present time the United States does not.

The Celsius scale was developed in 1942 by a Swedish astronomer named Anders Celsius. On the scale, zero degrees is the freezing point of water and 100 degrees is the boiling point of water. Between these two fixed points, Celsius divided his scale into 100 equal parts. In 1948, the ninth General Conference on Weights and Measures officially named the scale the Celsius scale.

Temperatures below the freezing point of water have a minus sign on the Celsius scale.