The Atmosphere

Why can I hear an AM radio station from hundreds of miles away at night but not during the day

At night, AM radio waves bounce off of a layer of the ionosphere, the ā€œFā€ layer, and can travel hundreds, if not thousands, of miles from their source. During the day, the same reflection of radio waves cannot occur because the ā€œDā€ layer of the ionosphere is present and it absorbs radio waves.


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