Maureen Broadway, age 12, of Jackson, Tennessee, for her question:

What is a moraine?

A moraine is a pile of debris left by a glacier. The great ice field collects all kinds of rocks, from pebbles to giant boulders as it moves on its way. These objects and smaller debris become frozen into the solid mass of ice. its the glacier slips down a slope or pushes out from its center, it carries this debris with it.

The edges of the glacier melt, dumping the debris as the solid ice becomes liquid water. This pile of dumped debris is called a moraine. The great glaciers of the ice age left moraines covering many square miles. However, none of these icy monsters reached as far south as Nashville, Tennessee.