TIL that the Heaviside Layer, the object of spiritual transformation in the musical “Cats”, is the RF reflective E layer in the atmosphere that lets skip transmissions propagate. The atomospheric E layer about 60-90 miles above the ground encompassed in the general layer known as the Thermosphere.

So the entire musical is essentially a bunch of cats trying to determine which one gets to DX long wave transmissions every year. Mind. Blown.

“a layer of ionised gas occurring roughly between 90km and 150 km (56 and 93 mi) above the ground — one of several layers in the Earth's ionosphere. It is also known as the E region. It reflects medium-frequency radio waves. Because of this reflective layer, radio waves radiated into the sky can return to Earth beyond the horizon. This “skywave” or “skip” propagation technique has been used since the 1920s for radio communication at long distances, up to transcontinental distances.”

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