| Term: | FRegion |
| Definition: |
A layer that contains ionized gases at aheight of around 150-800 km above sea level, placing it in the thermosphere.the F region has the highest concentration of free electrons and ionsanywhere in the atmosphere. It may be thought of as comprising two layers,the F1-and F2-layers. One of several layers in the ionosphere. Also known asthe Appleton layer. |