Tarde de domingo (y II): sonidos del espacio exterior

Hoy os traemos una curiosidad científica: sonidos captados del espacio exterior por diversos instrumentos espaciales (sondas, satélites, antenas...). En esta página de la Universidad de Iowa, tenéis toda una recopilación con la explicación de los fenómenos que los producen. Recomendada la selección del profesor Gurnett.
Nos quedamos con éste que mola un montón: Earth Multi-Hop whistlers (Sería algo como "silbadores terrestres multi-salto")

Y su descripción:
"Lightning-generated whistler waves in Earth's magnetosphere travel along closed field lines from one hemisphere to the other. The duration of the whistling tone can vary from one second to as little as one tenth of a second. The duration is related to the length of the propagation path. Each time the whistler wave approaches the base of Earth's ionosphere and is reflected, it travels back on a slightly longer path. A spacecraft traveling in the region of whistler propagation can detect the same lightning-generated whistler on successive reflections. The resulting sequence of descending tones will be separated by the travel time of the reflected wave (on the order of a second or more). The duration of each successive tone will become shorter as the path length becomes longer with each reflection"
Aquí está el espectrograma de los sonidos:
Inquietante.....