Resumen de Earth'S pulse
What happens in the bowels of the planet is a mystery, but we have a decent idea about the nature of the first few hundred kilometers beneath the surface. Tectonic plates, at most 250 kilometers thick, float on a layer of molten rock. Sometimes, those plates move suddenly against or away from each other, creating earthquakes. Pickrell talks about interferometric synthetic aperture radar, a satellite-mounted radar technique developed by NASA in the 1970s that bounces radio waves off Earth's surface.
