HAARP creates airglow by exciting electrons in Earth's ionosphere, similar to how solar energy creates natural aurora, with on and off pulses of high-frequency radio transmissions. The High-frequency Active Auroral Research Program (HAARP) creates artificial airglow by using radio pulses to excite electrons in the ionosphere, which is the region between Earth's surface and space. This process mimics the natural phenomenon that causes the northern lights. HAARP's Ionospheric Research Instrument (