All too often, Maxwell's equations are taught as mathematical abstractions without any connections to students' personal experiences. However, the interaction of radio waves with Earth's ionosphere provides an opportunity to apply Maxwell's equations in scenarios that have some connections to students' daily lives. A description of how electromagnetic waves propagate through a plasma is derived from Maxwell's equations. This description is used to show how the reflection of radio waves by the ionosphere can be used to enable long range radio communications, to establish that the Sun's emission varies over the solar cycle, and to measure physical properties of the ionosphere.
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