6/22/2021: Thousands of years ago, at different points in time, clouds of ash, rock and hot gas rushed across the Mojave and Sonoran deserts as two volcanoes erupted. These destructive events are long over. But their history is written in the lonely landscapes they ravaged. Volcanic dunes and other deposits hold debris from the ancient eruptions, as do craters marking the sites of the blasts — Ubehebe in Death Valley in the Mojave Desert in the U.S., and El Elegante in the Gran Desierto de Altar in the Sonoran Desert in Mexico.