That Booming You Hear in the Skies Over Yellowstone National Park? It Soon Could be the Sound of Artillery
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Ahh, the sounds of winter in Yellowstone National Park. The raspy rustle in the wind of dried leaves that forgot to fall from aspens. The trickling of a creek beneath its sheath of ice. The eruption of a geyser, the gurgling of mudpots. The explosion of a howitzer round as it smacks into a mountainside.