D-layer

The D-layer is a part of Earth's ionosphere, a region high in the atmosphere that contains charged particles. Located roughly between 60 and 90 kilometers above Earth's surface, the D-layer mainly affects radio waves, especially at lower frequencies. During the day, it absorbs and reflects certain radio signals, which can weaken or block them, while at night, it diminishes, allowing signals to travel farther. This layer plays a key role in radio communications and understanding how signals interact with Earth's atmosphere, especially for long-distance radio broadcasting and navigation systems.